Auto repair & maintenance

Books and taxes for engine rebuilders.

Long-block core exchanges, machine shop sublet work, dyno testing, and engines sold wholesale to other shops. Gus sorts all of it, an accountant checks every transaction, and you get one number a month.

Book a call What we handle
  • From $197 a month
  • An accountant on every transaction
  • Cancel whenever
JanuaryExample month
$19,000
what you made

January came in at $19,000. Two long-block cores finally shipped back for credit, so I netted them against what we paid for the reman parts instead of counting them as new income.

  • Wholesale engine saleWholesale sales
  • Machine shop sublet, boringSublet work
  • Piston and gasket kit orderParts and materials
  • Core credit, long-blockParts and materials
  • Dyno cell electricityShop overhead
Money in$79,000
Money out$60,000
Set aside for taxes$4,500
An example month. Yours will have your numbers.

Why your books are different

Engine rebuilder books go wrong on cores, sublet work, and who the customer is.

You sell to two different kinds of customers, the car owner and other shops buying wholesale, and every rebuild involves a core exchange, outside machine work, and sometimes a run on the dyno before it ships. A generalist bookkeeper sees one parts bill and one sale, and misses everything that decides whether a rebuild actually paid.

  1. 1

    Long-block cores carry serious money

    A core charge on a long-block engine can run into the thousands, refunded only once your old core ships back and passes inspection. Booked as pure income when it lands or a flat cost when it's paid, the real price of the rebuild disappears.

    What we doNets the core charge and its refund against the same job, so a rebuild shows its real cost, not a number that swings with the core.
  2. 2

    Machine shop sublet work isn't your labor

    Boring a block, decking a head, or balancing a crank almost always goes to an outside machine shop, and paid through the same account as everything else, that cost can blend into your own labor and hide what outside work is actually costing each rebuild.

    What we doKeeps machine shop sublet costs in their own category, separate from in-house labor, so each rebuild's real cost stays visible.
  3. 3

    Wholesale sales to other shops price differently than retail

    An engine sold wholesale to another repair shop earns a different margin than one sold and installed for a car owner, and lumped into one sales number, you can't tell which side of the business is actually paying you.

    What we doKeeps wholesale and retail engine sales in separate categories, so you can see what each side of the business actually earns.
  4. 4

    Dyno testing is a real cost most rebuilders undercharge

    Running a finished engine on the dyno before it ships takes shop time, fuel, and electricity that a generalist bookkeeper never separates from ordinary shop overhead, making it easy to undercharge for a step that protects your reputation.

    What we doKeeps dyno testing costs visible against the jobs that use it, so pricing reflects what proving an engine actually costs.

Your categories

The categories Gus keeps for an engine rebuilder.

Set up once for cores, sublet work, and two kinds of customers, you never pick a category, an accountant checks every one.

Money in

  • Retail rebuildsEngines rebuilt and installed for individual car owners.
  • Wholesale salesEngines sold to other repair shops, kept apart from retail.
  • Core creditsRefunds for returned long-block and short-block cores.
  • Dyno testing feesStandalone testing jobs for engines built elsewhere.

Money out

  • Engine parts and materialsPistons, gaskets, bearings, and rebuild kits.
  • Machine shop subletBoring, decking, and balancing sent to an outside machine shop.
  • Shop laborIn-house assembly hours, kept apart from sublet costs.
  • EquipmentEngine stands, hoists, and the dyno cell, logged so they get written off right.
  • Shop overheadDyno cell electricity, fuel, and testing supplies.
  • InsuranceGaragekeepers and general liability coverage.

What we watch for you

  • Core credit balance

    What's owed back on cores not yet returned, tracked so refunds don't get lost.

  • Wholesale margin

    What's kept on engines sold to other shops, tracked apart from retail rebuilds.

  • Sublet cost share

    How much of a rebuild's cost is outside machine work versus in-house labor.

  • The set-aside

    What you will owe, tracked every month, so April is a number you already knew.

Ask Gus

Things engine rebuilders ask Gus.

Text him like you would text anybody. He answers in plain English, and when a question is above his pay grade, an accountant looks and gets back to you.

The core credit on that long-block finally came through. Where does that go?

I netted it against what you paid for the parts, so it doesn't look like extra income, just the real cost of that rebuild coming down.

Should wholesale sales to other shops be tracked separate from retail rebuilds?

Yes, I already keep them apart. That way you can see what each side of the business actually earns instead of one blended number.

Do I need to charge for dyno time separately or fold it into labor?

Keeping it separate is the honest way, and I already track it that way, so pricing reflects what proving an engine actually costs you.

The tax side

The tax side of an engine rebuilding shop.

Most of what goes wrong here is core charges nobody nets against the part they belong to and sublet work blended into your own labor.

What your return has to get right

Your accountant signs it, so it gets done right the first time.

  • Cores and rebuild kits as inventoryA rebuild kit or core bought ahead of a job you haven't started is inventory, and its cost only counts against income once it's installed, not the day it arrived.
  • Engine stands, hoists, and the dynoShop equipment like engine stands, hoists, and a dyno cell can usually be written off the year you buy it. Bonus depreciation is back to 100 percent for property bought after January 19, 2025.
  • Contractor 1099s for machine workA machine shop you send boring, decking, or balancing work to, paid $2,000 or more in 2026, gets a 1099-NEC by January 31. Gus keeps that list running all year.
  • The pass-through deductionMost owner-operator shops can take up to 20 percent of business profit off their taxable income, and it comes out right when the books are right all year.

Deductions engine rebuilders miss

Your bookkeeper knows what to look for in your statements. You never have to.

  • Piston ring compressors
  • Torque plate rentals
  • Dyno cell electricity
  • Engine stand maintenance
  • ASE certification fees
  • Garagekeepers insurance
  • Shop towel service
  • Waste oil disposal fees
  • Uniform rental service
  • Shipping on core returns

General information about 2026 federal rules, not advice for your business. Your accountant looks at your actual numbers before anything gets filed.

All year, not just April

An engine rebuilder's year, kept every month.

Rebuild volume runs unevenly all year with wholesale orders on their own schedule. Your taxes come on a schedule. Your team keeps you ahead of both. Every month in between, your bookkeeper closes the books and speaks up the moment something looks off.

  1. January

    Plan the year

    Last year's return gets started, the 1099 list for machine shops is ready, and you get a monthly set-aside so April isn't a surprise.

  2. April

    Filed. Done.

    Your return is filed and signed. No surprise bill, because the set-aside has been running since January and matched what the shop actually made.

  3. July

    Halfway check

    Where you stand, what you will owe, and whether a run of wholesale orders changed the number this year.

  4. October

    Before winter breakdowns

    Cold weather brings more engine failures. Before the rush, Gus looks at equipment worth buying and moves worth making before December.

What you get

Starts at$197a month

What you pay depends on what your business needs, and it does not move after that, busy season or slow. No hourly bills, no surprise invoices, no setup fee.

Book a call
  • Monthly bookkeeping

    Every transaction sorted into categories set up for engine rebuilders. You never categorize a thing.

  • An accountant checks every transaction

    Real review, every month, before your books close. Not a spot check.

  • Your business tax return, filed

    Prepared, reviewed, and signed by that same accountant every year.

  • The monthly number

    What you made, what you spent, what to set aside for taxes.

  • Your own bookkeeper

    A real person assigned to your business, in the app whenever you need them. No hold music.

  • On your books all year

    Every month, not just in April. Your team speaks up whenever something is worth your attention.

  • Cancel any time

    No contract. No cancellation call. Your books are yours.

Straight answers

Questions engine rebuilders ask first.

How does Gus handle the core charge on a long-block engine?

He nets the core deposit against the refund once your old core ships back and passes inspection, so the rebuild shows its real cost instead of a number that swings with the core.

Can Gus keep wholesale sales to other shops separate from retail work?

Yes. Wholesale and retail rebuilds are tracked in separate categories, so you can see what each side of the business actually earns, not one blended sales number.

Machine shop work costs me a lot per rebuild. Is that tracked separately?

Yes. Sublet costs for boring, decking, and balancing stay apart from your own labor, so you can see exactly what outside machine work is costing each engine.

Should dyno testing time be billed separately from assembly labor?

It's the more honest way to price it, and Gus already tracks dyno time on its own, so you can see what proving an engine actually costs before it ships.

My books are a mess from doing them myself. Is that a problem?

No. Send the bank statements you have. Gus sorts them, the accountant checks them, and most owners know where they stand inside a week.

Is a real accountant checking my books?

Yes. You get your own bookkeeper, Gus does the first pass on every transaction, and an accountant checks every one before your month closes. That same accountant prepares, signs, and files your business return. Goatkeeper is not a CPA firm, and we never pretend a person looked when they did not.

What does it cost, and can I cancel?

It starts at $197 a month, depending on what your business needs. No setup fee, no hourly bills, no contract. Cancel any time from the app, and your books go with you.

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Book a call

Pick a time. That's the whole signup.

Fifteen minutes with a real person on our team. They look at where your books are, tell you straight what it takes to get caught up, and get you set up on the spot if it fits.

  • $197 a month to start
  • An accountant on every transaction
  • Cancel whenever