Cash flow and stock turn for independent dealers

Why a profitable forecourt can still run out of money, how to measure return on capital rather than margin per car, and the mistake that quietly kills growing dealerships.

Updated 1 August 2026 · 5 min read · Written for UK independent dealers

A dealership can be profitable on paper and unable to pay its bills. It happens regularly, usually to businesses that are growing, and it happens because profit and cash are different things that move at different speeds.

The two numbers

Margin per unit is what you keep on a car. It is the number dealers quote and the number that feels like performance.

Stock turn is how many times a year your stockholding cycles. If you hold £150,000 of stock and sell £750,000 of cars in a year, you turn five times.

Multiply them and you get what actually matters: the return your capital produces in a year. A dealer keeping £1,000 a unit and turning four times makes the same as one keeping £500 and turning eight — but the second one has half as much money at risk at any moment, and far more flexibility.

Margin per unit is a measure of your negotiation. Stock turn is a measure of your business. The second is worth more and gets far less attention.

Where the cash goes

The money in a used car business is nearly all in three places.

Stock. By far the largest. Every car is cash sitting still.

Work in progress. Cars bought but not yet listed — awaiting collection, in prep, being photographed. This is the most expensive stock you own, because it is costing you and cannot possibly sell. A dealer with eight cars in prep for three weeks has a substantial sum earning nothing.

Debtors and timing. Finance payouts, part-exchange settlements, trade sales awaiting payment.

The largest controllable one is prep time. Cutting the average time from purchase to listed from eighteen days to eight releases real money without selling a single extra car.

Why growth eats cash

This is the mechanism that catches people out, and it is counter-intuitive: a growing dealership consumes cash even while making profit.

You sell more, so you buy more. You buy more, so more money sits in stock. The profit on the cars you have sold arrives after the cash for the cars you have bought has left. Grow fast enough and you can be simultaneously more profitable and closer to insolvent every single month.

The warning signs are specific:

• Stock value rising faster than sales
• Average days in stock creeping up while unit count grows
• Reaching for finance to buy stock rather than to fund a specific opportunity
• Delaying paying for prep work

None of those look like a crisis individually. Together they are one.

Measuring it properly

Three figures, monthly, on one line:

Stock value. Total retail value of everything on the forecourt.

Cash tied up. What you actually paid, including fees, transport and prep. This is the real exposure and it is a different, smaller number than stock value — do not confuse them.

Value past its window. The retail value of units past their normal selling window. This is your early warning system, and it moves months before your accounts do.

Then the derived one: stock turn = cost of cars sold over the year, divided by average cost of stock held. Under four is slow. Six or more is genuinely good for an independent.

Improving turn without giving stock away

Cut prep time. The single biggest lever and the one most within your control. Book the MOT before the car arrives. Have a valeter on a standing arrangement rather than a favour. Photograph the day it is ready, not the following weekend. Every day saved is a day of capital returned.

Price properly in week one. A car priced right from the start either sells or tells you something is wrong early, while the information is still cheap. A car priced optimistically wastes its best four weeks — the weeks when it is freshest in the listings — and then needs discounting anyway.

Buy in your band. Cars in your normal price range sell to your existing customers at your normal speed. Stepping up a band ties up more money for longer, and the margin rarely compensates.

Exit dead stock on a schedule. A written rule — at 2× the normal window, it goes to trade — converts a slow asset back into cash you can deploy. Dealers without a rule keep cars for a year.

Do not over-order into a good month. A strong month tempts you to buy heavily. If the strength was seasonal, you have bought stock into a falling market with money you will want back.

Floorplan and stocking finance

Stocking finance is a legitimate tool and a genuine risk, and the difference is entirely in what you use it for.

Used to buy specific, fast-turning stock that you have checked properly, it accelerates a business that already works. Used to cover cars that are not selling, it converts a stock problem into a debt problem and buys time you will spend making the same mistake.

Two disciplines if you use it: keep the interest cost visible per unit so it appears in your margin calculations, and never let funded stock age past your normal threshold — funded dead stock is the most expensive thing on any forecourt.

A working monthly review

Ten minutes, same day each month:

1. Stock value, cash tied up, and unit count
2. Average days in stock — and the distribution, not just the mean
3. Value past its window, in pounds
4. Cars in prep, and the average age of prep
5. Units sold, and average retained profit
6. Stock turn, rolling twelve months

Watch the direction of travel more than the level. Days in stock rising for three consecutive months is a signal worth acting on, whatever the absolute number says.

The single habit

If you take one thing: measure the pounds tied up in stock past its window, monthly, and act on it.

It is the earliest reliable indicator that buying has drifted, it is visible months before it reaches your accounts, and acting on it — trading out the tail, releasing the cash, buying something that turns — is nearly always the right move even when it means booking a loss.

Booking a loss on one car is a bad afternoon. Running out of cash is a bad year.