To me, and everyone’s thread hold to pain is different, if test flight was not a possibility I would want the seller to demonstrate key things.

Engine runs and makes power under load for x time.

Avionics work

Controls work correctly.

Logs are correct

Physical condition is airworthy, i.e. no physical damage and fabric is good.

Hell, it doesn’t have to be flown to make laps around the taxi ways or to do a run up.

Refusal means rock bottom pricing as there’s something to hide, large or small it’s something that someone is not willing to be honest about.