How to Analyze a Rental Property Deal in St. Louis: Step-by-Step

The Most Important Skill in Real Estate Investing

Every experienced investor will tell you the same thing: the money is made at the acquisition, not the sale. Buying right is the entire game. And buying right means knowing how to run the numbers before you make an offer — accurately, quickly, and consistently.

Most beginning investors either skip the analysis entirely (gut feel investing) or overcomplicate it with 40-tab spreadsheets that take hours to complete. Neither approach works. Here is a practical, repeatable framework for analyzing a St. Louis rental property deal in under 30 minutes.

Step 1: Establish the After-Repair Value (ARV)

The ARV is what the property will be worth after a full renovation, based on comparable sales in the same neighborhood. This is the single most important number in your analysis — everything flows from it.

To establish ARV, pull 3–5 recent sales (ideally within 90 days, within 0.5 miles) of similar properties — same bedroom count, similar square footage, similar condition. Focus on sold prices, not list prices.

In St. Louis, ARV for a renovated 3-bedroom in North County typically runs $130,000–$165,000. In South City, $145,000–$195,000. In St. Charles County, $200,000–$280,000. Know your submarket.

Step 2: Estimate Rehab Costs

Rehab estimation is where most new investors go wrong — they underestimate. Use this framework for a standard St. Louis value-add deal:

Roof replacement (if needed): $8,000–$14,000 for a standard 3/2
HVAC replacement: $4,000–$7,000
Kitchen update (cabinets, counters, appliances): $8,000–$15,000
Bathroom update (per bathroom): $4,000–$7,000
Flooring (full house): $4,000–$8,000
Paint (interior + exterior): $3,000–$5,000
Windows (if needed): $400–$600 each
Landscaping and curb appeal: $1,500–$3,000

Add 15% contingency to whatever total you reach. St. Louis housing stock is old — you will find things during demo that were not visible at inspection.

Step 3: Calculate Your Maximum Allowable Offer (MAO)

The MAO formula is the investor's core acquisition tool:

MAO = (ARV × 0.70) − Rehab Costs

The 0.70 multiplier builds in your profit margin and holding costs. For a property with a $155,000 ARV and $40,000 rehab estimate:

MAO = ($155,000 × 0.70) − $40,000 = $108,500 − $40,000 = $68,500

Do not pay more than your MAO on a BRRRR or flip deal. If the seller wants $85,000 and your MAO is $68,500, the deal does not work at that price — move on.

Step 4: Project Monthly Cash Flow

Once you know the acquisition and rehab numbers, project your monthly cash flow as a buy-and-hold rental:

Gross rent: Pull 3–5 active rentals of similar properties in the same zip code
Vacancy allowance: Subtract 8% of gross rent (approximately 1 month per year)
Property management: 8–10% of collected rent
Property taxes: Check the county assessor — St. Louis City and County vary significantly
Insurance: $800–$1,400/year for a standard single-family in St. Louis
Maintenance reserve: 8–10% of gross rent
Mortgage payment: Based on your financing (DSCR loans typically run 7.5–8.5% at 75% LTV)

Net cash flow = Gross Rent − Vacancy − Management − Taxes − Insurance − Maintenance − Mortgage

Target minimum: $200/month net per door. Better deals produce $300–$500.

Step 5: Calculate Key Return Metrics

Two numbers matter most for a buy-and-hold deal:

Cash-on-Cash Return: Annual net cash flow ÷ Total cash invested. Target: 8–12% for St. Louis value-add deals.

Equity at Purchase: ARV − (Purchase Price + Rehab). This is your immediate equity position. A well-executed BRRRR leaves $30,000–$50,000 in equity at the refinance point.

Running Deals Faster With Experience

The framework above takes time to learn but becomes second nature with repetition. Experienced St. Louis investors can run a preliminary analysis on a property in 10 minutes — enough to know whether to pursue due diligence or pass.

At Midwest Investor Services, every deal we present to investor clients comes with a complete underwriting package. If you want to see how we analyze deals and what the current pipeline looks like, reach out and we will walk you through a live deal.