I was going to tell you how you could upgrade to an AP, but then I checked out your thread about it and it sounds like you have plenty of people helping you out and most of them know more than me.
The buying a small DVC resale I know all about though. We bought a small resale (50 points) last fall at the Boardwalk with the plan of transferring points from other members so we would have enough points for large reservations. We've only done 1 point transfer so far and it worked out just fine. However you should make sure you really look into this before you take the plunge because there are lots of restrictions. You can only do 1 transfer a year so you have to make sure you get enough points in that transfer. You have to find a member that will do the transfer (I found mine on the DVC rental board). And there is always some risk involved. Most transfers involve giving half the money first then receiving the transfer, then paying the other half. There is nothing but trust stopping someone from taking the money you've sent via paypal and running. So if you aren't willing to do do transfers I'd say a small DVC isn't for you. 50 points even with banking and borrowing will not be enough for the kind of vacations you're considering. And if you're going to pay extra for the housekeeping that is also something to consider. I think it's at least $50 a day for a 2 bedroom villa. (But don't quote me on that.) The primary reason we bought into DVC wasn't financial. It was an emotional investment for me so that I knew there would never be "a last trip". Maybe we'll save a few bucks over time, but frankly at this point it would be just as cheap to rent points from on owner (though that involoves trust as well). The upcoming trip will be my 3rd time renting points and we've always had a good experience with it. So that is my take on the small DVC resale thing. Obviously I'd do it (we did), but I'd make sure you understood what you were getting into.
Ok so that may be more than you wanted to know, but that's what you get for mentioning it