Repair Shop Bookkeeping: Invoices, VAT and Records

Bookkeeping is the least popular part of running a repair shop and one of the most useful. The same records that satisfy HMRC also answer the questions a shop actually needs answered: what a repair really costs, which lines are profitable and whether the prices are right.

None of it requires an accounting qualification. It requires a consistent habit, a few fields per job and a monthly routine that takes an hour.

Why does bookkeeping matter in a repair shop?

Many small transactions, few large ones.

A shop might complete twenty jobs a week, each with a part cost, a labour element, sometimes a deposit and occasionally a return. Without records, the only visible number is the money in the bank, which tells you nothing about which work is making money.

With records, the picture changes quickly. Parts cost per repair, return rates by line and the actual margin on each repair type all become visible, and those are the numbers that decide pricing and stock.

What should every job produce?

An invoice with the part, the labour and the payment method.

Each job needs a dated invoice showing what was done, which part was fitted, what was charged and how it was paid. Where a deposit was taken, the invoice should show it and the balance, rather than a single figure that hides the arrangement.

The intake record and the invoice together form the job file. That file is what supports a warranty claim, a supplier return and the pricing review described in pricing a repair so the parts margin survives.

How do you handle VAT?

Register when you must, reclaim properly.

VAT registration becomes compulsory once turnover passes the threshold, and it can be voluntary before that. A registered shop reclaims the VAT it pays on stock, so the input tax is a timing difference rather than a cost; the current rules and the threshold are published at register for VAT.

The practical consequence is that a registered shop should keep supplier invoices rather than just receipts, because it needs the VAT breakdown to reclaim anything. A box of unclaimed input tax is the most common avoidable loss in a small business.

How do you record deposits and balances?

As two entries against one job.

A deposit is not income when it is taken; it becomes income when the work is completed. Recording it as a payment against the job, with the balance settled at collection, keeps the accounts accurate and matches what the customer was told.

That structure also protects the shop in a dispute, because the job file shows exactly what was agreed. The reasoning behind taking deposits at all is described in taking deposits on high-value repairs.

How do you track stock and cost of sales?

Record the cost against the job.

The number that matters is what the part cost when it was used, not what the shelf is worth at the end of the year. Recording the part cost against the job produces an accurate cost of sales figure and, in turn, an accurate margin.

That requires knowing which part went into which device, which is the same batch discipline that supports supplier claims. The stock side of it is described in planning stock by the numbers.

What expenses can be claimed?

Anything wholly and exclusively for the business.

Tools, equipment, consumables, parts, software, insurance, training and the costs of running the premises all fall into the same category, provided they are for the business. Mileage for business travel and a proportion of household costs where a shop trades from home are the two areas most often done badly.

The test is purpose rather than appearance, so a tool used only for repairs is straightforward and a laptop used for both needs apportioning. Keeping the receipts and noting what each purchase was for removes the question.

What about customer data in your records?

Keep the job, not the content.

Records should show what was repaired, which part was fitted and what the customer paid. They should not include personal data from the device, and any temporary copies made during a repair should be deleted when the job closes.

The obligations are set out under the Data Protection Act 2018, with practical guidance for small organisations published at ICO guidance for organisations. Retaining a customer’s photographs in the shop’s own files is a risk with no business benefit.

How often should you reconcile?

Monthly, and against the bank rather than against memory.

A monthly reconciliation matches invoices and payments to bank entries, catches anything missed and produces the margin figures while they are still useful. A shop that reconciles once a year is doing archaeology rather than management.

The routine takes about an hour once it is established. Its real value is that it produces the numbers for a pricing and stock review while there is still time to act on them.

What software do you need?

Invoicing and payment records, nothing more.

Most small shops need invoicing with a stock or parts field, and a way to record expenses. A repair-specific system adds job tracking and customer history, which is worth having where the volume justifies it.

The mistake is buying software with more capability than the shop will use. A simple system that is actually maintained beats a comprehensive one that is not, and the choice can be revisited as the business grows.

What does an accountant need from you?

Complete records, delivered on time.

An accountant needs sales, expenses, stock movements and payroll information, provided in a form they can work from. Where the records are complete, the fee is smaller and the advice is better, because the accountant can see what the business is actually doing.

The wider obligations that come with a trading structure are summarised at running a limited company. Whichever structure applies, the same principle holds: records kept during the year cost far less to process than records reconstructed afterwards.

What are the common mistakes?

Mixing personal and business spending, and losing receipts.

A single bank account used for both makes every reconciliation harder and every expense question ambiguous. A separate business account, even for a sole trader, removes that problem at no real cost.

Losing receipts is the second, and it is entirely avoidable. Photographing a receipt when it is received takes seconds and produces a record that survives a faded till roll, which is a genuine problem for parts bought at trade counters.

The numbers are worth reading, not just filing. A monthly look at margin by repair type shows which work pays for the bench and which quietly does not, and that is the information behind a pricing change.

Records matter beyond tax as well. An insurer asking about turnover, a supplier questioning a trade account or a customer disputing a repair all depend on the same paperwork, and a shop that keeps it properly answers each of those questions in minutes.

The monthly review deserves a fixed agenda. Turnover, cost of parts, margin by repair type and the value of stock on the shelf are the four figures that matter most, and they come straight from records that were kept at the time.

Keeping records useful during the year is mostly about naming things consistently. A part recorded as “screen” on one job and “display assembly” on another cannot be counted, and a supplier recorded three different ways cannot be reviewed. Consistency is what turns a pile of invoices into information.

Supplier invoices are the records most often misfiled, and they are the ones VAT depends on. A single folder, physical or digital, with the invoices in date order makes the quarterly return a short task rather than an afternoon of searching.

At the end of the year, what an accountant needs is completeness rather than sophistication. Sales, expenses, stock and payroll information, all present and consistent, produce a smaller bill and a clearer picture of the business than any amount of software used inconsistently.

Where the records have fallen behind, the fix is to work forwards rather than backwards. Starting from this month and keeping the current period accurate is more useful than spending three evenings reconstructing last year, and the older records can be tidied afterwards.

Getting help early is cheaper than getting it late. An accountant who is asked to set up a simple system for a new shop charges less than one who is asked to untangle two years of mixed transactions at the filing deadline.

What is the one habit that keeps the books clean?

Record the job on the day it is done.

Invoices raised at collection and parts recorded against the job while the device is still on the bench produce complete records with no extra effort. Anything left until the end of the month is being reconstructed rather than recorded.

Around it sit the ordinary disciplines: a separate business account, supplier invoices kept for VAT, monthly reconciliation and a data policy that keeps customer content out of the shop’s files. Replaced parts are waste under the Waste Electrical and Electronic Equipment Regulations 2013, parts placed on the market fall to the Office for Product Safety and Standards, and retail customers keep their rights under the Consumer Rights Act 2015.

Keeping the current period accurate is what makes those numbers usable during the year, which is the point of doing the work at all.