Vette, as a Realtor and licensed mortgage loan officer, the term "fixer upper" sends up a red flag for me. If by fixer upper you mean a home that needs updating, painting, and some minor repairs, that's one thing. If however you mean a home that need immediate repair to be occupied (leaky roof, non functioning kitchen, unfinished projects, just to name a few conditions) that's another situation.
A home that needs minor repair can be financed with a standard, low down payment, conventional or FHA loan. A home that has major issues will require special financing. Google "FHA 203k". If you would like to know more feel free to email me at firstname.lastname@example.org.