Cheryl,
You should be able to add a full bed. There is a thread out there on this subject, you'll find it if you search for it. As far as making the twin beds up: open the drapes to the back window, then you slide the mattress up on to the night stand(if you don't open the drapes, the mattress will drag across them) and then it's easier to make them up.
Also if you add a quality full size air mattress(doesn't have to be a Bearbed) it will be easier to move onto your new full size frame. I found that the quality air mattresses are awesome!
As far as the "free" seminar, I feel you're on the right track. The higher end rv parks have the folks with the extra cash to lay out for those nice "toys"
.
I'm sure you'll hit on something!!
Good luck-John