Your estate agent values the house at £300,000.

That's a rather satisfying number.

Unfortunately, it isn't the amount you'll have available for the next house.

First, the mortgage has to go.

Then the estate agent wants paying.So does the solicitor.

Then somebody mentions an EPC.Then removals.

And if you're selling a leasehold flat, there's a fair chance another piece of paperwork arrives with a fee attached to it.

Before deciding what you can afford to do next, work backwards from the sale price.

Start with the estate agent

Estate-agent fees can be one of the largest selling costs.

The source material for this article puts typical fees at around 1% to 3% of the selling price, although agents use different charging models.

Some charge a percentage.

Some charge a fixed amount.

Some include photography, floorplans and accompanied viewings.

Others may charge separately for particular services.

So don't ask only:

“What's your fee?”

Ask:

“What will I actually pay, including VAT, if you sell my house?”

Then ask what's included.

On a £300,000 sale, even a seemingly small percentage difference can turn into a meaningful amount of money.

Then add the legal bill

You'll need a solicitor or licensed conveyancer to handle the legal work involved in transferring ownership.

The source material puts seller legal fees broadly around £800 to £1,800, although the actual amount depends on the property and work involved.

A straightforward freehold house may be one thing.

A leasehold flat with a managing agent, service charges and additional paperwork can be another.

Ask for a written quote and find out what could be added to it.

If you're selling leasehold, ask about the cost of the management information your buyer's solicitor is likely to need.

That's a particularly irritating bill to discover after you've already mentally allocated every penny from the sale.

Check whether you already have a valid EPC

An Energy Performance Certificate, or EPC, gives the property an energy-efficiency rating.

An EPC normally lasts for ten years.

If yours is still valid, you may not need to buy another one.

If it has expired, factor a replacement into the selling budget.

This is one of those jobs where five minutes checking the existing paperwork could save you ordering something you already have.

Ask your mortgage lender for the important number

Your online mortgage balance isn't necessarily the exact amount required to clear the loan when you sell.

Ask the lender for a redemption statement.

That tells you what will need to be paid to clear the mortgage, including any applicable early-repayment charge or exit fee.

This can matter enormously if you're selling while still inside a fixed mortgage period.

Suppose you sell for £300,000 and owe roughly £150,000.

It's tempting to think:

£150,000 equity.

Not quite.

The amount available to you comes after the mortgage is cleared and the other selling costs have been paid.

That's the number your next move needs to be based on.

Selling somewhere that isn't your main home?

Tax may need adding to the calculation.

If you're selling a buy-to-let, second home or another property that hasn't simply been your main residence throughout, Capital Gains Tax may be relevant.

That's sufficiently dependent on individual circumstances that it isn't something to estimate from somebody else's house sale.

Check your own position before committing the proceeds elsewhere.

And you still have to move out

Then comes the physical move.

Van.

Boxes.

Possibly packing.

Possibly storage.

Possibly the moment when somebody looks at the enormous wardrobe and asks whether it comes apart.

We covered those moving-day surprises separately, but they still belong in the overall calculation of what selling and moving will cost you.

Don't forget the £100 jobs that breed overnight

Cleaning.

Gardening.

Touching up paint.

Fixing the dripping tap.

Replacing something that finally breaks two days before the photographs.

Perhaps putting some furniture into storage so buyers can actually see the spare bedroom.

None may be particularly frightening individually.

Collectively, they can become another four-figure dent in the budget surprisingly quickly.

That doesn't mean turning your Peterborough home into a showroom.

It means deciding what genuinely needs doing and putting a number beside it.

Do this calculation before the For Sale board goes up

Write down:

Expected selling price

minus mortgage redemption amount

minus estate-agent fee

minus legal costs

minus EPC if required

minus leasehold or management charges if applicable

minus removals and storage

minus pre-sale jobs

minus a buffer for the thing you haven't thought of yet

What remains is far more interesting than the headline sale price.

Because that's the money you can actually use for whatever comes next.

Property Speak — Translated

Conveyancing — The legal work involved in transferring ownership of the property.

EPC — Energy Performance Certificate. It gives a home an energy-efficiency rating and is normally valid for ten years.

Mortgage redemption statement — A statement from your lender showing the amount required to pay off your mortgage on a particular date.

Early-repayment charge — A fee some mortgage deals charge if you repay the loan, or a large part of it, before an agreed period ends.

Leasehold management pack — Information about a leasehold property, service charges and management arrangements that is commonly needed during a sale.

If you've sold a Peterborough home, which cost surprised you most once all the bills started arriving?

Tell us in the comments.