A "purcahse survey" run about $20.00 per foot here in FL.
Don't go for the cheapest surveyor, that is like shopping for the cheapest parachute......
The surveyor may turn on the electronics, but I doubt he is going to "test" each piece.
The radar you can check out your self: If it paints an echo somewhere out there, it is probably working.
Ya need to do a radio check on the SSB, try channel 824 and ask for WLO for a radio check..If they say "loud and clear", ya are in good shape..
If they can;t hear ya or don't respond, that could be a problem.
Try the autopilot on different headings, if it can hold the heading most of the time, it is a good beginning, but you won't know for sure until ya tried it in following seas, with a following wind.
Stay out of the surveyors face while he is digging around, but make sure you pick his brain when he takes a breather....
He works for you and nobody else, you can ask him anything.
Good Luck.