What should I actually check when buying a used caravan privately?

Water damage is enemy number one — press around windows, roof seams, and the floor near the bathroom for any softness or musty smell; soft spots mean expensive repairs. Check the chassis and A-frame for rust, look at tyre age (the date stamp, not the tread), test every appliance (fridge on all power sources, hot water, gas, pump), and open/close all windows and the door. Confirm the compliance plate weights match what's advertised, check the brakes work, and always verify there's no money owing via a PPSR check before you pay.