The City of San Bernardino is to be avoided, so are Rialto and Fontana. I've heard it referred to as "the armpit of southern California". I think that's correct.
I've seen and heard nice things about Rancho Cucamonga (to the west).
These things are always generalities and there are exceptions, if you can find them.
For 18 months, are you looking to lease/rent or buy?
San Bernardino has heat and terrible smog in the summers. The Los Angeles smog gets blown out there by the prevailing winds and gets trapped in the basin.
The get some hellacious winds in the fall (Santa Ana winds).
San Berdoo is surrounded by mountains.
The Cajon pass gives access to the high desert areas referred to earlier.
There are ski areas in the surrounding mountains at Wrightwood, Lake Arrowhead and Big Bear. Mountains are as high as 11,000 feet, steep, rugged terrain contrasting sharply with terrain in Ohio.
LOTS of other recreational opportunities, too - camping, hiking, mountain biking, dirt biking, cross country skiing, boating,... It's the Angeles National Forest and the San Bernardino National Forest.
Anyone know the daily commute time from Crestline to SBD?
If it were me, I'd start looking in the better parts of Redlands and Rancho Cucamonga. I'd also look up towards the mountains over to the NE and NW.
Look on Zillow.com to get some pricing ideas.
I hope this helps in some way.