Hey, Should be do-able w 2 meals from QS, and some left for a snack, but I'd probably budget a little more just in case. Like maybe 60. Look over the QS menus to get idea of prices. Many are in mid teens, but some creep up to near 20. Butterbeer is around 8.00 plus tax, and the ice cream at Florian's can range from $7-9, etc. so maybe just add a little extra for snacks, etc. There are GREAT QS options for sure for lunch/dinner. We also always do breakfast in the room, or on the go.
and also, I really enjoyed Aventura. We've stayed there a couple times there now. It's kind of a small room, but still enough space, and close enough to SF to take their boat, or just walk, or catch boat at RP. Have a great trip!!!