Greenhouse suggestions?

Ok so my parents are getting sketched out about the plants getting too big so i want to get them a greenhouse so they are somewhat concealed.

Ive been looking on ebay and they have alright looking ones for 100 shipped. But I dont know weather or not it would get good amount of sun to the plant.

I was looking at these

http://cgi.ebay.com/LARGE-SIZE-HIGH-QUALITY-GREEN-HOUSE-WITH-SHELVES-HUT_W0QQitemZ270383792069QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3ef4213fc5&_trksid=p3286.c0.m14

http://cgi.ebay.com/NEW-12x7x-7-GREENHOUSE-OUTDOOR-GARDEN-GROW-GREEN-HOUSE_W0QQitemZ290339806375QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item439999dca7&_trksid=p3286.c0.m14

You could always look up "DIY greenhouse" on google... I'm pretty sure you can make your own with pvc pipe and poly for a lot less.