What to check before you buy

On a used caravan the mechanics are rarely the problem. Water is. Almost every expensive fault you will meet starts as a leak nobody took seriously in time.

Damp, before anything else

Take a moisture meter. It costs about as much as a meal out and tells you in five minutes what no photograph will. Measure the walls at floor height, in the corners, under the windows and around the roof lights.

Under 15% is dry. Between 15 and 20% means "watch it". Above 20%, walk away — or take the cost of rebuilding a wall off the price, which is not small.

Signs without a meter: brown staining at the joints, rippled wallboard, a shut-in smell that does not clear after airing, a floor that gives slightly underfoot near the door.

Body and roof

• Get on the roof if the structure allows. That is where the sealant cracks, and where nobody looks.
• Check the window seals: hard and crazed means you will be replacing them.
• Open and close every roof light and every service hatch.

The systems

• Gas: ask for a valid safety check. If there is none, the cost of one is part of the negotiation.
• Water: fill the tank and let the pump run. Listen under the floor.
• Fridge: run it on all three supplies for twenty minutes. Gas is the one that fails first.
• Heating: run it even if you are viewing in August.

Chassis, tyres, brakes

Tyres carry a date on the sidewall — four digits, week and year. Over six years they are replaced whatever the tread looks like. Check the spare too; it is almost always the oldest on the vehicle.

The paperwork

• Registration document in the seller's name.
• The chassis number on the plate matching the documents.
• For imported vehicles: the invoice and the de-registration document from the country of origin.
• Check for any outstanding finance or lien.

The last question

"What have you repaired in the last two years?" A seller who has looked after the vehicle has a long answer and the invoices. One who shrugs has told you, without meaning to, everything you need to know.