Yes, life happens. My wife and I have both been through divorces that hit us pretty hard financially and our credit wasn't good. We were able to work a couple of different deals (one on a used unit a few years ago) and another on a new motorhome in April. As Chuck said, the more you can put down, the better as the lender will see it as less risky.
Interestingly enough, even my own credit union (whom I have been with for 25+ years) would NOT give us a loan. It didn't matter that I went in person to apply and had all of my paperwork in order to document the issues on my credit report. They still saw any loan to me as a risk and acted just like a larger bank would. Our original loan was through a much smaller local credit union, and the second (much larger) loan was through a bank with a sizable down payment and faster repayment schedule (15 years vs. typical 20 years.)
Although we are not full time now, we will be in another year or so.
So, a little homework and some perseverance will help. It CAN be done! Good luck!