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Recently a number of listeners to the podcast have asked about evaluating real estate investments. They want to know how much rent they would need to charge for a specific property to make it a “good” investment. The good news is that evaluating the numbers is really simple.

Today we’ll look at 3 key ratios you can run on any property. I’ll use the numbers from one of my investment properties to walk through how each of these ratios work. The results of these simple formulas will help you evaluate a potential real estate investment you may be considering. Frankly, I use just the first of these three formulas, which you can calculate in your head, to evaluate a property in about 20 seconds flat.

Related: Investing in commercial real estate with RealtyMogul is an exciting way to multiply your investment in ways that aren’t often possible with small-scale real estate.

Table of Contents:

My Property

The property I’ll use in this article is a 3 bedroom one bath ranch I bought in 2009. Here are the numbers:

Purchase Price: $42,000
Rehab & Other Costs: $25,800
Total Investment: $67,800
Amount Financed: $64,000
Cash Invested $3,800
Rent: $895
HOA: $0
Monthly Mortgage Payment: $403.69 (P&I)
Taxes: $156.00
Insurance: $33.00
Estimated Repairs: $66.58 per month
Estimated Annual Vacancy $74.55
Net Operating Income (excludes mortgage payment (P&I): $6,778.44 (annually)
Total Monthly Outflows (including mortgage): $733.82

3 Key REI Ratios

Rent Ratio

The rent ratio is calculated by dividing the monthly rent by total cost of the property (purchase price + financing costs + rehab costs):

rent ratio = monthly rent / cost of the property

For example, if the total cost of a property were $100,000 and monthly rent were $1,000, the property would have a rent ratio of exactly 1%. In the example of my property above, the rent ratio is a bit higher at 1.32% ($895 / $67,800).

Generally, we look for a ratio of at least 1%. Some investors that I know look for ratios as high as 2%. Obviously the higher the ratio the better, all other things being equal. What I found, however, is that for a single family home in a good school district in central Ohio (where I invest), 2% is not feasible.

Note that this ratio does not factor in expenses. This is important to understand. We don’t buy properties with HOA (homeowners association fees) and we are able to finance the purchases at competitive rates. As a result, I am very comfortable using this as an initial assessment of a property.

The next two ratios, however, do factor in costs.

Cap Rate

Short for capitalization rate, the cap rate enables you to evaluate and compare properties without factoring in financing. The formula is simple:

Cap Rate = Net Operating Income / Total Cost

Net Operating Income, or NOI for short, is based on annual numbers and is gross rents minus all expenses, but excluding the P&I portion of a mortgage payment. For many properties, expense include taxes, insurance, repairs and vacancy.

Note that it is critical to estimate the cost of repairs and vacancy. You’ll see above the estimates that we use for both of these costs. Running the numbers for the above property yields a cap rate of 10% ($6,778.44 / $67,800 = 10%).

Generally, a cap rate of at least 6% or better is a must. While we don’t always calculate a cap rate for our investments (the rent ratio is enough), our properties fall in the 8 to 10% range.

Note that the cap rate does not factor in the cost of financing. Our third and final ratio does.

Cash on Cash Return

The final ratio is the cash on cash return. You calculate this ratio by dividing your cash flow by the cash you have invested in the property:

Cash on Cash Return = Pre-Tax Cash Flow / Total Cash Invested

Pre-tax cash flow is simply annual rents less all cash outflows (including the P&I of the mortgage payment. Apply this formula to my property above yields a cash on cash return of more than 50% ($1,934.16 / $3,800 = 50.9%).

Most look for a ratio of between 15 and 25%. For us, the actual ratio is meaningless. As you can tell, the more leveraged you are, the higher the ratio. But this doesn’t make an investment a reasonable one. We absolutely look at the actual cash flow we believe a property will generate. A positive cash flow is a must. But calculating a cash on cash return ratio is of little value to us.

If you use other metrics to evaluate a real estate investment, share them with everybody in the comments below.

Author Bio

Total Articles: 1080
Rob founded the Dough Roller in 2007. A litigation attorney in the securities industry, he lives in Northern Virginia with his wife, their two teenagers, and the family mascot, a shih tzu named Sophie.

Article comments

Kenneth says:

Good article, Rob. I used my Google Chrome browser Instapaper add in to save the article to Instapaper for future reference. I don’t own any rental properties now, but in the future – who knows!

Jeff says:

I also use the ratio of estimated property value divided by annual rents. Takes some extra work on rental property historical trends in your area to understand what ratio range is a reasonable purchase area and what ratio range is signalling a time to sell. However, the extra effort removes the emotion and allows one to be objective. Bought a property in San Diego at a ratio of 12 and sold when the ratio climbed to 25 and this got me out before the crash. Hope this helps others.

Erin says:

Hi Rob,
I think you mentioned in this podcast you’d be doing a future podcast on taxes as related to real estate investing. Did I misinterpret, is it still forthcoming, or is the topic covered in one of your recent shows?


Rob Berger says:

Erin, yes I’m working on it!

Michel says:

Hi Bob, I found this is be very helpful and easy when figuring out the value. However what about a 15 year mortgage? You would be negative for a few years but closer to paying off the home. I’m having trouble figure out what’s a good deal in my area. I’m looking at places between 300-450k in Northern California. Things are going up and perhaps it’s a bad time to buy. Rents go from 1700-2100. Therefore, the rent would not cover all my expenses with either a 15 or 30 year mortgage (maybe come close with a 30) but in the long run the house would cost you more. Would you stay away from this type of deal? How do you go about evaluate the right time to buy? We also thought about renting it for several years and perhaps move in and live in it. House prices where we live are just way too much – Bay Area. Thanks for your input!!

Oliver Kocoski says:

Hi Bob
I invest in a similar way as you have mentioned in your podcast, but for me to get good returns is by working on the property my self. If I were to subcontract the work my returns are horrible. Wondering if you guys are doing the same thing or subcontracting the work.

John says:

Bob, please tell me how you calculated the estimated annual vacancy of $74.55. Thanks