We got a 12 foot vuly after recommendations from friends. With net, tent, ladder, anchor kit and skirt to go around the bottom (to keep the dog out!) I think it was about $800 -$900 delivered.
It's great for an adults and couple of kids (or an adult to show how high he can jump
) but the 10foot one would be fine as well. If I had the room I'd get the 10 instead of the 8 foot one.
The neighbours got a cheap 14 foot one, because their old one was broken. The old one only lasted a year or two before it buckled out of shape.
Whatever you do, get it level - otherwise the welds have too much strain on them and everything gets bent out of shape.