My newest hurdle

So I finally called the management company to check the status of my rental application (after not having heard from them after two weeks). Apparently, they are only willing to accept my application if I'm willing to pay the first and the last TWO MONTHS of rent! Over $2,000!!! Who does that? First and last would be difficult, but why the hell are they asking for three months? I mean, I get it. My rental payment history is not perfect, but it's imperfect in that I end up paying LATE. And by LATE, I mean a few days, maybe a week. This is mostly because of our wacky pay schedule. The thing is I do PAY! I have never skipped out on a lease or been evicted or even come close to being evicted. When I mentioned this, the woman (who was not the ultimate decision-maker) said it was because of a negative rental reference, i.e. SCA choosing not to renew my lease. This makes me wonder if I am missing something else here as to why my lease isn't being renewed. Truth is I never asked once I got the letter. I just assumed it was because of the late payments. I can't imagine what else it would be. I'm not noisy. My apartment's a bit messy, but it's not a garbage house. As far as I know, no one has made any kind of complaints about me being noisy or a problem neighbor, so what's the deal? This just seems so unfair and vaguely suspicious. To ask someone for three months of rent in advance just seems sketchy, but I really don't have the time to try to find something else. And the inventory being what it is, I might not even find anything else. This all sucks in so many different ways. Off I got to Craigslist to see if anything else strikes me. Ugh! I kinda wanna cry!!!!