[Richard]

Drain about 5 gallons of the coolant into a clean container for reuse. Take off the top rad hose and run an endoscopic camera into the radiator.

Depscan is a good brand on amazon.

Bus grease monkey has a few videos where he does the same.

Wheels off, look at brakes and rotate wheels to check for bearing roughness.

check around potty and windows for soft wood.

Welcome to the madhouse.