From Estimate to Final Invoice: One Bathroom Remodel, Every Number

The job is Clamp's published 5x8 hall bathroom: same layout, a new 60x30 tub with a tiled surround, a vanity, toilet, fan, two light fixtures, paint and 28 square feet of porcelain floor tile. The estimate prices it at cost, line by line, in the order it is built.

That is 53 lines across ten trades, led by tile ($3,007.83) and plumbing ($2,940.00). No overhead and no profit sit in any line. The cost breakdown shows every one.

Then the markup goes on once, to the whole cost:

The 1.50 is an illustration: it carries 23 1/3% for overhead and 10% net profit. Your own markup comes from your own overhead and goal.

The proposal turns the estimate into the agreement the job is built to: the scope, the $17,698.76 price, the payment schedule and the terms. The customer signs it in the portal.

From here on, the signed agreement is the only price that counts. Work that isn't in it is a change order, priced and signed before it's built. This bathroom had none, so the contract stays $17,698.76 to the end.

The milestones split the price into payments, each tied to an event in the job, never a percentage complete or a date.

Two choices shape it.

The deposit equals the allowances. $4,749.85 is exactly the selections: the tub, vanity, fixtures and tile you order before work starts. The customer pays for what you buy for them before you buy it.

Each stage is billed when it starts, not when it ends, at its value less the selections the deposit already paid for. The invoice guide works each one; the demo stage, for example, is $7,740 of work at the selling price less $2,250 of selections the deposit covered.

The final payment is the 2% held for the walkthrough: $353.98. You never finance the customer's job, and the last check is small enough that a punch list item doesn't hold your profit hostage.

The documents move the job. The tracking records show what it actually took, and each one counts a cost once. The full idea is in cost, owed and paid.

Floor tile. The estimate carried 30.8 square feet at $5.50, $169.40. Four boxes were bought for $231.00 and one went back for $57.75. The receipt and its return leave the line at $173.25, $3.85 over.

The countertop. A purchase order to the stone sub committed $296.40. When the work was done, the bill made it $296.40 of job cost. The contractor paid $150.00 by check and owed $146.40. The cost stayed $296.40; the payment only settled part of the debt.

Labor. Hours were logged by role each day and costed at the loaded rate.

As each stage starts, its invoice goes out from the schedule, and each payment is recorded against its invoice. After the carpentry stage, the customer has paid four invoices:

Nothing on the job is late if each invoice goes out when its event happens. If an event slips, the invoice moves with it; if a payment is late, the invoice guide says what to send.

At the final walkthrough, closeout reconciles the last bill to the contract, every signed change and every payment.

It matches the final payment on the schedule to the cent. That is the test of the whole chain: if the final balance surprises anyone, a change, a credit or a payment was missed somewhere upstream.

Closeout also holds what isn't money: one signed punch list, lien releases where your state or contract requires them, and the warranty and care records handed over in writing.

Once the job is closed, job costing compares actual cost with the estimate, by category.

The job ran 1.5% over. Gross profit before overhead came to $5,726.11 instead of the planned $5,899.59.

Almost all of the miss is labor. That is what the next bathroom estimate learns: the real hours, not the hoped-for ones. The price can't change after it's signed. The next estimate can.

Every number above connects to the one before it.

The bathroom is Clamp's published example, not a bid or a market average; the purchases, payments and actual costs are illustrations on it. The method page puts the same job beside the rule for each stage.