Your most immediate need is a place to live...so focus on finding the rental first. If a landlord is ok with rent-to-own, that's gravy, but it's not something you should expect. After all, someone is a landlord because they want the rental income, not because they want to get rid of their property...at least not yet. :-)
Rentals happen fairly quickly - usually within a few days. If you have credit issues, there are ways to position your application so that you have a better shot at your app being accepted. Also, the big players in the rental business have less at risk than an individual landlord, and they are more likely to accept a marginal application.
One of the things I'd suggest for the long term, if you truly want to purchase down the road, is to work with a lender who specializes in helping you clean up credit issues. Few loan officers offer this service, but those who do are well worth knowing.
You've had a number of agents respond so I'll leave it here. If you'd like to get in touch or discuss further, my office number is 703-547-8451. Calls to this number forward to my cell.
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