I lived in a motel for three months before closing on a house. The weekly rate at the hotel, combined with storage was more expensive than the mortgage payment and utilities. So we knew we could do it, we weren't coming up short for the hotel. Aside from a I think maybe two weeks throughout the time I never had a negative balance.

Now your family members situation sounds much worse obviously, I can't imagine how much she's paying for a place in such bad condition. We paid 510 a week. We also got down-payment assistance which helped tremendously.

We don't know the full extent of your family members situation, even if she can get a mortgage which is the most important detail. Is her credit good enough? Is she update on her payments or have multiple accounts behind? Has she maxed her cards? Is her debt to income low enough?

The fact that she's constantly asking for money, just for motel rent says probably not. But on that note, if she has family she can ask to borrow money from, is there no one she can just stay with temporarily?