I hear their ads saying that regardless of credit and negative equity, they can get you in a vehicle for lower than your current monthly payment. How true is this?

I have to agree with the rest here. For financed vehicles, that may be true - but it's only because they are going out 72 months on the vehicle and perhaps they can get a sub-prime lender to over-allow on the LTV because they give the lender volume. And only then, that would be dependent on how much would be the "fee" the lender charges the dealership to take the buy. I know Fuccillo is all about volume, so they probably make little over whatever the holdback is on the invoice. That being said, if you're 630 or under, don't waste your time going there and trying to lease their vehicles. KMFC has a tiered leasing program and anything less than 630 is an automatic decline. Period. For financing, because there are many lenders, both prime and sub-prime, lower scores are fine as long as the mechanics of the deal are decent to get conditional approval from a lender AKA LTV & DTI are within an acceptable range. In borderline cases, this is where the dealership's "influence" come in handy.

To tell you the truth I had 2000 to put down on a car and my payoff for my current car is 5000 they didnt want my car or to pay it off and my payment would have been 450-475 per month

Yeah if you have bad credit expect a payment of 400 or more

If you have a low credit score, forget it.