There is actually a hotel in San Diego that is relatively inexpensive. I think it is a fancy 'hostel'. I think.
here is a hostel link
http://www.sandiegohostels.org/ but not the place I was directed to.
This is it
http://www.500westhotelsd.com/ .
It actually looks pretty nice. What is sort of shocking is that the prices seem high but with other hotel prices in Downtown, they probably aren't.
So....one could do San Diego on $300. Enjoy the free touristy places, ride the ferry early in the a.m. {before 8:30} and get a free return ticket {commuters, they don't ask} . There is a selection of museums free on Tuesdays........I mean, it can be done. Carpool and that saves gas and gas money. ;0)