The best area would be around the University, in zip code 93710:
The houses were built in the '70's mostly.
A lot have been foreclosures.
There have been a lot of fixers and flips.
And, NO, $100,000 is pretty much limited to the seedier areas, south of town.
I would venture that you're in the $150,000 and $160,000 range, (starting), and that would necessitate some repairs and updates.
Some are 3/1 but most are 3/2, 1200 to 1700 sqft. with 2 car garages and 1/4 acre lots.
Many parents buy the houses for their student kids, and sell them after 4 years.
Good luck and may God bless