You can engage the services of a mobile RV tech to do this sort of thing. Some will give an ad hoc check-out, while others will only work to specific instructions, i.e. do x, y, and z. We have checklists in the RVforum library on things to look at when buying an RV. You could use those, or a subset, as the basis for hiring an RV tech for an inspection. Expect to pay by the hour, including travel time.