@Van Tran, I echo a lot of what was said by @Jill F. and @Richard F.. First, what type of property is it (poorer neighborhood where lower credit scores are norm or nicer area where higher credit scores are norm)? Second, "why" is their credit score low? I've found, with "aspirational" tenants, where they had legitimate reasons for a lower credit score (instead of this is just a way of life), they will do almost anything they can to improve their credit scores if given a chance. The only way to know is to dig into it via the application/screening process. I usually advise them, when they ask to fill out an application, that they need to divulge anything that might come up on the background check (I use simplescreening.com). If they do so and it matches what comes back, then I say "let's talk more about this"..
Bottom line: I've had some of my best tenants over the past 15-20 years of doing this were those that I would not have rented to them if a low credit score was the reason why I didn't rent to them. However, I put most of them on a "6-month probation" lease up front and let them know I'm taking a chance and please prove the credit score wrong. Yes, it took a lot more time up front as I would check in on them every couple of weeks to see how they were doing, but they seemed to really appreciate that someone believes in them and is rooting for them.. Many of those tenants have been incredibly loyal (and grateful)..