I also have run into trouble since I own two condos and they won't count the income from roommates as part of my monthly income even though I have leases with them.

It seems like kind of a pain to have this rotating cast of roommates.

He gave me their phone number and I talked to the guy, he said he's getting a plan in place and may have a place to go but his roommate might not and he still didn't have a for sure date of move out.

(The owners aren't really affected though as long as they pay their rent.)One has roommates who are not allowed and aren't on the lease and he admitted that he has no income while I was explaining that he has to get them to move out.

I guess I’m wondering if this is a good idea considering it’s mostly all my cash and I’ll be renting to my girlfriend and her roommate.

To do a mixed rental you'd have to find a certain special kind of roommate/tenant for your other room. 

My gut tells me you'd do much better just getting a roommate on a normal lease.

Is there any chance that you could buy it and get her a roommate?

Pick up a second job and a roommate and start saving money.

So don't ignore single family homes unless you don't like roommate situations.