What is the average price to rent a single family 3 Br house or an Apt. in San Fernando, CA.?

It looks like the average or median price for a 3-bedroom in and around San Fernando is $1800. The range seems to be from about $1600 to $2000, which is not too bad for the LA area overall. I can't speak to the quality of the places but you can look them up yourself at a site like PadMapper and see what you can find.

Good luck with the home/apartment hunt.