Where to stay in San Diego?

I will be in Anaheim next week and am planning on driving down to San Diego Friday afternoon to catch a class and was wondering if anyone had a recommendation on a good but affordable place to stay Friday night? I have to drive back to the Bay Area on Saturday so I would like to be able to get a decent nights sleep before the drive.

Google motel 6 mission gorge San Diego,it's at 4370 Alvarado canyon rd, that one says 66 a night and it's literally right down the street. Or for 46 there's a days in that's like 2 or 3 exits up at 5343 Adobe falls rd. I'd post up the screen shots but for some reason it's weird on my phone.

Thanks for the suggestions. I realized that my wife had enough points at a major hotel chain for me to stay free, so going that route. Looking forward to checking out SD and 10th Planet there.