It all depends on how much of a down payment you will have. My credit is horrible! But I'm going to have 30% to put down on a house so it doesn't matter as much. If you have less to put down you'll need a higher credit score. Shop around for credit cards and get another. Make sure it reports to more than one credit agency (Experian, Trans Union, & Eqifax). Try not to get too many inquiries. They lower your score. So know which one you want to go with before you apply. Once you get it, use he credit card for things you would normally pay cash for. Like gas, groceries etc. And then pay it off completely at the end of each month. Of course trying to pay the negative stuff off will help too! I'm in the process of buying a house at the moment and I paid a credit adviser to give me most of the same advice I just gave you!
There is also a good website to monitor it too. www.truecredit.com It charges you about $15 a month and you can cancel it at any time! I found some stuff I didn't even know I had on there and was able to resolve it before it got too bad!
On a different note: If you could possibly wait and save up at least 20% down, You'll be saving a lot more money in the long run because they will charge you some extra insurance/fees with out it. And, of course the more you put down the less your payment will be, the less your score will matter and the better the interest rate etc.!
Sorry for the long post!! Good Luck!
(If you would like the info for my credit guy let me know! He worked miracles in a short amount of time for me!)
My over-paid mortgage broker and credit advisor!