Bookkeeping for Mobile Detailers and Mechanics: Mileage, Supplies and Tips

What mobile detailer and mechanic books need to track

A mobile detailer or mobile mechanic runs from the van. You drive to the job. You use supplies from the van. You finish the job and drive to the next one. Sometimes a customer adds a tip. Each part of that day needs its own line in the books so the profit per job is real.

When you mix it all into one cost pile, you can not tell which jobs paid and which ones cost more than they brought in. The long drive across town ate the margin. The heavy supply use on a big detail made the job cost more than you thought. The tips hid the fact that the base price was too low. You can read more about how we keep these lines apart on our bookkeeping page.

A clean month shows each job with its own income, its own mileage, its own supplies, and its own tip. The profit per job is real. The next price quote gets easier because the real costs are clear.

Here is what a clean job looks like.

How mileage shows up in your books

Mileage is the biggest hidden cost for a mobile business. You drive to every job. The gas, the wear on the van, and the time on the road all cost money. If you do not track miles per job, that cost sits in one pile and you can not tell which jobs were close and which ones were across town.

The clean way is to log the start miles and end miles for each job. The difference is the miles for that job. When you tie the miles to the job, you can see which jobs cost more to reach. A job that pays the same but takes twice the drive is not the same job. The books show it.

The messy way is to log the total miles for the day and never split them. Now every job looks like it cost the same to reach. The far job that ate your morning hides in the pile. You can read more about how we track mileage in our mileage log guide.

Here is how to keep mileage clean.

• **Log the start miles and end miles for each job: ** not just the total for the day.
• - **Tie the miles to the job name: ** so you can sort by job and see the real drive cost.
• - **Track the miles the same way every month: ** you do not need it perfect, you need it consistent.
• - **Watch for far jobs that cost more to reach: ** the margin on those needs a closer look.
• - **Keep the log in the van: ** write it down before you drive to the next stop.

When the miles tie to the job, the drive cost shows up on the right line. When they sit in one pile, every job looks the same.

How supplies tie to the job

Supplies are the wax, the polish, the soap, the towels, the degreaser, the oil, and the parts you use on the job. You buy them in bulk and use them a little at a time. The way you tie them to the job changes what your books show.

The clean way is to hold bulk supply buys in a supplies account first. When you use product on a job, the cost moves to that job. A detail that uses three bottles of polish shows more supply cost than a quick wash. A repair that uses two quarts of oil shows more parts cost than a filter swap. When the cost ties to the job, the margin per job is real.

The messy way is to book every supply buy to one flat supplies line and leave it there. Now your supply cost looks the same every month, even though some months you did twice the jobs. You can not tell if one product is eating your margin. You can read more about how we track supplies by job in our plumbing truck stock guide. The same idea works for a detail van or a mechanic truck.

Here is how to keep the costs clean.

• **Hold bulk supply buys in a supplies account: ** until a job uses them.
• - **Move the cost to the job that used it: ** not to one flat line.
• - **Log the supplies the day you use them: ** not at the end of the month from memory.
• - **Watch for product price changes: ** a higher wax cost changes your margin.
• - **Compare jobs at month end: ** see which one eats more supply per dollar.

When the supplies tie to the job, your margin per job is real. When they sit in one pile, every job looks the same.

How to keep tips out of the sales line

Tips are a common source of mistakes in a mobile business. A customer is happy with the detail or the repair and adds a little extra. That extra is not sales. It is a tip. If it sits in the sales line, your income looks higher than it is, and your prices look right when they might be too low.

The clean way is to give tips their own line. When a customer adds cash or a card tip, it goes to a tip income line, not the job sales line. The job income shows what you charged for the work. The tip shows the extra. When you look at the two side by side, you can see whether your base price is right or whether the tips are hiding a price that is too low.

The messy way is to book the tip into the sales line with the job payment. Now the job looks like it paid more than it did. When the tips dry up one month, the sales line drops and you can not tell why. The tip was propping up the number.

Here is what to keep separate.

When tips sit in their own line, the sales line shows your true price. You can see if the work pays on its own or if the tips carry it.

How a route day shows up in your books

A route day is the heart of a mobile business. You load the van, drive to three or four jobs, use supplies at each one, collect payment, and drive home. Each part of that day needs a line.

The clean way is to book each job as its own batch. The income for the job goes to a job income line. The miles for the job go to a mileage line. The supplies used go to a supply cost line. The tip goes to a tip line. When you run the profit and loss by job, you can see which job was the good one and which one ate the supplies and the drive.

The messy way is to book all the income to one general sales line, all the miles to one total, and all the supplies to one flat line. Now every job looks the same. You can not tell if the morning jobs pay and the afternoon jobs lose money. You can read more about how we handle these route days on our payroll page if you have a crew on the road.

Here is how to keep route days clean.

• **Book each job as its own batch: ** so the income and the costs sit together.
• - **Tag each job to a job name or class: ** so you can sort by job.
• - **Log the supplies used that day: ** not at the end of the month from memory.
• - **Log the miles for that job: ** the van log is your proof.
• - **Log the tip for that job: ** so it sits apart from the sales line.

When each job sits on its own batch, the margin per job is real. When it sits in one pile, every job looks the same.

How the month end close works

At month end, every job needs its lines added up. The income, the mileage, the supplies, and the tips all pull together into one job total. The difference between the income and the costs is the profit for the job. When the jobs roll up, you see the month by job and by class.

We start with the bank. We match each job payment to the deposit that landed. We tie each supply buy to the job that used it. We tie each mile to the job that drove it. We keep the tips in their own line. Then we add up the month by job and send you the profit and loss report, a balance sheet, and a cash summary. The jobs sit inside the report.

Here is a simple month end check.

• **Match each job payment to the bank: ** every deposit cleared.
• - **Tie each supply buy to the job: ** not to one flat line.
• - **Confirm each job carries a class tag: ** so you can sort by job.
• - **Keep tips in their own line: ** not mixed into sales.
• - **Run the profit and loss by job: ** see the income, the costs and the margin per stop.

When the close runs every month, the business stays clear. When it skips a month, the jobs stack up and the next month is harder to close.

A situation we clean up

The tips that hid the price problem

A mobile detailer runs four or five jobs a day. Every job payment, every tip, and every supply buy lands in one general sales line and one flat cost line. The mileage is logged but never tied to a job. At month end, the owner can not tell which jobs paid, which ones cost too much to reach, or whether the tips were hiding a base price that was too low. A month with fewer tips shows a sales line that dropped, and the owner can not tell why.

Here is how we handle it. We set up a class for each job in QuickBooks Online. We go back through the open months and tag each payment to the job that earned it. We tie each supply buy to the job that used it. We split the mileage by job. We move the tips to their own line. When we are done, the owner can run the profit and loss by class and see each job with its own income, its own mileage, its own supplies, and its own tip. The base price shows on its own, and the owner can see which jobs pay and which ones need a higher quote.

Mistakes we fix

• Every job payment booked to one general sales line with no job tag
• Every supply buy booked to one flat supplies line
• Mileage logged but never tied to a job
• Tips mixed into the sales line so income looks higher than it is
• A far job that costs more to reach but looks the same as a close one
• A tip that propped up a job where the base price was too low
• No profit and loss by job run at month end

Common questions

How do I track mileage per job? Log the start miles and end miles for each job. The difference is the miles for that job. Tie the miles to the job name so you can sort by job and see the real drive cost. You do not need it perfect, you need it the same way every month.

How do I keep tips out of the sales line? Give tips their own income line. When a customer adds cash or a card tip, book it to the tip line, not the job sales line. The sales line shows your true price. The tip line shows the extra.

How do supplies tie to the job? Hold bulk supply buys in a supplies account first. When you use product on a job, move the cost to that job. Log it the day you use it, not at the end of the month from memory. When the cost ties to the job, your margin per job is real.

How does a route day show up in my books? Book each job as its own batch. The income, the mileage, the supplies, and the tip each get their own line. Tag the batch to a job name so you can sort by job and see which stop pays.