We are a family of 5 also, and as someone said the rooms availlible for a fam of 5 are exxtremely limited EVERY WHERE... Most hotel chains dont allow 5 in a room. Sucks.
I am part of the crowd that would love to see DVC change the occupancy limits of a one bedroom to 5. We would still get a two bedroom, but when the kids are older, we would like to downsize to a 1 bedroom, because we wont be in our room as much.
I love Debbie's idea of asking your guide to put it in writing. I doubt he will though.
lenshanem mentioned two queens in a one bedroom... OOOHHH I would love that, but not so much for me and the kids, but for our yearly girl trips! LOL
With all that said, if you can only purchase 150 points, I would bank and borrow, go every other year, in a 2 bedroom.
Let us know what your guide says if you ask him to put it in writing.