Hull Out What can I do
I dont know how they do surveys where you live but here in San Francisco they tend to pull the boat out just before lunch, leave it in the slings and go to lunch. The surveyor does his thing over lunch time and the spash the boat as soon as they resume work.
The price for this sort of haul is a lot less than they charge for blocking the boat on dry land for a paint job.
I''d suggest you have the yard powerwash the bottom when they haul it and put it in the water. I would not invest in a bottom paint job until you know you are going to buy the boat. Until you have the results of the survey, you wont know that.