Last updated October 19, 2026
The items that end up costing $15,000 to $40,000 are almost never the ones that catch your eye during a showing. Here is a room-by-room checklist of what to look for before you write any number on an offer.
Hidden repairs like a failed sewer lateral are one of the most common post-closing surprises in St. Louis, and one of the biggest drivers of what buyers regret most after buying a cheap house in St. Louis. A sewer scope is part of due diligence on every St. Louis home, not just older ones.
From my St. Louis showings and inspections. Costs are 2026 expected costs from my repair cost guide.
Start outside: the roof, gutters, tuckpointing, foundation cracks and grading. Then the basement for signs of water and the sewer cleanout, the ages of the furnace, AC and water heater, the electrical panel brand, the attic, and interior red flags like fresh paint everywhere, sticking doors and bouncy floors. The expensive problems are almost never the ones that catch your eye. Room-by-room checklist ↓
Sewer lateral failure is one of the most common expensive surprises. Clay tile laterals crack, offset, and get infiltrated by tree roots over decades. A camera inspection before closing costs $150 to $300. Replacement typically costs $4,000 to $12,000 and can exceed $15,000 in some cases. The second most common is basement water intrusion combined with failed tuckpointing on brick homes. The basement ↓
Yes. Get one on every St. Louis home, whatever its age, as part of your due diligence. Clay tile sewer laterals are endemic in St. Louis's older housing stock, newer lines can still have root intrusion or damage, and lateral failure is one of the most common post-closing surprises buyers face. The camera inspection costs $150 to $300 and tells you the condition of the pipe before you are committed to the purchase.
White mineral deposits on the walls (efflorescence), staining or a waterline at the floor, patched or painted-over cracks and fresh basement paint. Find out where the water came from and what was done about it. The basement ↓
Look at the electrical panel door -- the label will say Federal Pacific Electric or Stab-Lok. These were common in St. Louis homes built between 1950 and 1985. If you cannot access the panel at a showing, ask your agent to confirm the panel brand before you write an offer. Replacement typically runs $2,000 to $4,000. Mechanical systems ↓
Most buyers start evaluating a home the moment they walk through the front door. I start in the driveway. The exterior tells you more about a home's maintenance history than anything inside, and in St. Louis specifically -- where brick construction dominates -- the outside is where the money lives.
Walking a house this weekend? Pull up my walk-through tool on your phone. Flag what you see room by room, and it adds up 2026 expected repair costs as you go. Save or email your results so you can compare houses later.
Spotted something outside? Tap it to open the walk-through tool with it flagged: roof, tuckpointing, chimney, siding, windows or foundation. You’ll see the 2026 expected cost.
In St. Louis, the basement is where you find the expensive problems. Clay soil that expands when wet creates lateral pressure on basement walls. Old sewer laterals back up and fail. Water intrusion is common and ranges from cosmetic to structural. Take your time down here.
Water or sewer questions? Flag basement waterproofing, the sewer lateral or foundation repair in the walk-through tool, and get the scope during your inspection.
Old systems? Flag the HVAC, water heater, electrical panel or supply plumbing in the walk-through tool to see what replacement would cost.
Found knob-and-tube or roof leaks? Flag a full rewire or a roof replacement in the walk-through tool.
Cosmetic work adds up too. Flag paint, drywall, flooring, a kitchen update or a bath update in the walk-through tool, then save or email your results to compare houses.
This checklist is not designed to talk you out of buying a house. It is designed to make sure the price you offer reflects what is actually there -- not just what the staging and fresh paint make you feel.
Every item on this list has a cost range. Understanding which items are present and roughly what they will cost to address gives you the information to make a defensible offer and negotiate from a position of knowledge rather than hope.
The goal going into a showing is not to find a perfect house -- those are rare. The goal is to understand what you are buying well enough to price it correctly and know when to walk.
Cost ranges for every major repair item in the St. Louis market. St. Louis Home Repair Cost Guide → → How to turn what you find into a defensible offer number. How Repair Costs Should Affect Your Offer Price → → What happens after you are under contract -- and how to use the report. What Happens at a Home Inspection in St. Louis → →Outside
Look for missing or curling shingles, granule loss and a sagging ridge line, and ask how old the roof is. St. Louis roofs typically last 20 to 25 years. An asphalt roof replacement runs $8,000 to $20,000 in 2026 expected costs. Exterior ↓
Horizontal cracks in poured concrete and stair-step cracks in block or brick point to lateral pressure, which is more serious than vertical hairline cracks. Neither is automatically a deal-breaker, but both need a professional evaluation. Should I buy a house with foundation cracks? →
Negative grading means the ground slopes toward the foundation instead of away from it. This channels rain and snowmelt directly against the foundation and into the basement. Correcting it runs $500 to $3,000 in 2026 expected costs, from simple soil regrading to more significant drainage work. It is one of the easiest things to spot during an exterior walkthrough and one of the most overlooked.
No -- most older St. Louis brick homes have tuckpointing that is at various stages of wear. The question is whether it has failed to the point of allowing water intrusion, and how much work needs to be done. A single failing facade is a $1,500 to $4,000 repair. A full house that has not been touched in 30 years is a $5,000 to $15,000 project. Factor the scope into your offer rather than treating it as automatic grounds to walk.
Inside
Plan on replacing it. Most insurers won’t cover a home with active knob-and-tube wiring, and many lenders require it to be removed before closing. Look for it in the attic of homes built before 1940. The attic ↓
Yes. Missouri has elevated radon in many areas. A test runs $100 to $150 during the inspection period, and a mitigation system runs $800 to $1,500 if you need one.
It’s worth a second look, especially in a basement or on ceilings. It doesn’t mean the seller is hiding something, but it means you can’t see what was underneath. Interior red flags ↓
This is one piece of the St. Louis home buying process. See how it all fits together:
📚 Complete St. Louis Buyer Guide →
Grew up in South St. Louis, lived in Dogtown for 6 years, now in South County. You'll find us at Wellspring on Lindbergh on Sundays. I'm not selling you a house — I'm showing you how to think about buying or selling a house.
Questions about what you are reading? I answer personally -- no team, no handoff.