Since this is a used unit, in your driveway camping, open the beds and hose them down really good. While you do that have someone inside looking for leaks on the seams and where the tenting is joined to the body of the trailer. If it was well taken care of you shouldn't have any leaks. You can treat the seams with seam sealer for tents if you see leaks on the seams.
If you have to close up wet, just use an old bath towel to dry the vinyl as good as you can. The little bit of moisture that is left will dry by the time you re-open them when you get home. That's after a rain. If you have to pack while its raining, open the beds at home and they dry off in an hour or so. The vinyl is not like trying to dry straight canvas. In 13 years of owning hybrids we've only had to pack up in pouring rain 3 times.
Treat the bed seals with a UV protectant twice a year. Our last hybrid was 10 years old when we traded it and the seals looked like new.
We're in our 50s and still love having a hybrid. Have fun!
EDIT: Looks like my timing was bad, I repeated much of what elwood58 said!
