Some basic tips:
Shop around.
St. Louis has many "fixer-upper" houses available for very reasonable prices, if you are willing to put in some "sweat equity." Consider foreclosures, LRA (city-owned) property, HUD-owned property and those marketed as investment property.
Gut rehab or moderate rehab? Depending on your tastes and needs, you may find a house that only needs a little work or one that needs an extensive rehab with all new systems. Find others who have done this and talk to them. Contacts can be made through neighborhood associations, city friendly realtors and the Rehabber's Club.
Use tax credits and rehabber mortgages. The State of Missouri offers tax credits for home improvements and historic rehabilitation that can reduce your rehab cost. The HUD 203k loan program and FannieMae HomeStyle mortgage are designed for rehabbers.
Find a hardward store nearby. Your local hardware store can provide personalized service and attention to detail on your rehab project. Finding a hardware store nearby will also save gas and time. Take time to think about all the steps and materials that you will need for your project to reduce frustration and unnecessary trips to the store.
Environmental Considerations. Renovating an older home often means addressing lead paint and/or asbestos removal or abatement. Protect the health of yourself and your family by following safe handling guidelines. Hire contractors certified to handle lead paint or asbestos. Educate yourself before beginning your project. "An ounce of prevention is worth a pound of cure."