Some one told me that if I had a LARGE downpayment, I could still get a loan even if my credit is bad.
Someone gave you bad advice. Your ability to purchase your new home is based on information from your credit report. It is normally judged by a FICA score. If you have a long list of derogatories (slow pay to collections), then unless those are resolved satisfactorily to the lender, you will not get a loan no matter how much you put down.
That said, You know how well you will stack up in that department. If the credit info is fairly old(more than 2-5 years) and you have steady verifiable income over the last 2 years, put that large amount of DP you have in the bank and make a minimum DP. Get the loan that satisfies your personal needs with as little out of pocket as you can. You will need to show a certain amount of income in your bank account over a period of time to prove to the lender you are stable and can manage your money.
If you have enough cash on hand to cover loan costs and 6 months mortgage IN THE BANK, then I am fairly certain you can get a loan. The interest rate to start out may not be the lowest in comparison to someone with A1 credit and NO derogagatories, but you can probably still get qualified and get your home.
That is why I advise you to seek a person like me to help you get started and get pre qualified. There are plenty of loan officers available in Eugene Oregon. I have been there. It is a beautiful place. I hope you get a nice home. ( And clean up your credit mess. You can see now why, can't you?)