When purchasing a home your loan qualification is all about your debt to income ratio, credit score, and available funds.
Have you looked into different loan programs such as FHA, VA, or Conventional? Each program has its own qualifications.
It sounds like you have a generous down payment, but don't forget about closing costs. Depending on taxes and lender fees (these fees are very important, make sure to shop around!) you could be looking at anywhere from $4,000 to $8,000. A great agent or a lender can figure closing costs for each and every home you look at.
Also when talking about collections all types of unsecured debt has to be paid in full prior to closing on your home. Any unpaid collections will most likely attach themselves to the property in the form of a lien. The lender will not take the risk of the collections becoming liens and effecting the title of the home.
To be honest with you a lender is the absolute best person to talk to about qualification. As long as you go to the right person you will have all of your questions answered quickly along with getting officially pre-qualified. I can provide you with a few great loan officers, or you can talk to the bank that you trust on a day to day basis with your checking account and various other accounts. Who ever you decide make sure to choose a local lender because of the way Douglas and Sarpy County handle taxes.
You should start looking when you feel comfortable you are ready to buy. Test the waters now, and get a feel for the market. Understanding the market is so important in the home buying process. I would be more than happy to walk you through the many steps involved in buying a home, along with providing you with listings in your ideal area. Please feel free to contact me at email@example.com or 402-595-8857.