If it will help, I would like to contribute my actual experience to the discussion. I have several rental properties spread across three different states – all professionally managed.
For the year 2006, my Net Operating Income was 42.5% of my actual rental income, putting my operating expense at 57.5%. Debt service was 37% of actual rental income. After operating expenses and debt service I am left with 5% cashflow for the year.
I included in my operating expenses everything directly attributed to my rentals that takes money out of my pocket that is not debt service. I also do not include any “overhead” expenses for a home office. Replacement costs, leasing fees, commissions, legal fees, property management fees, repair and maintenance costs, utilities, postage, homeowners association dues, condominium association dues, and pest control are all included in my operating costs.
Vacancy is not included because I used actual income in my calculations. If I am doing a proforma for a property to purchase, I use one month vacancy allowance per year. Contribution to a replacement reserve is not included because I used actual costs in my calculations. If I am doing a proforma for a property to purchase, I allow a replacement reserve amount equal to the average monthly per unit replacement cost for my entire rental portfolio for the previous year.
I think my numbers are typical, though I did have a higher than normal vacancy rate this year because of several new acquisitions. Most years my cash flow is between 10% and 15% of actual rents. I could lower my operating costs by self-managing or by purchasing fewer condos with high association fees. However, I prefer to concentrate on the big picture.
There are three reasons to invest in rental property. I credit Ron Starr for this. He uses the abbreviation CAT for Cash Flow, Appreciation, and Tax Benefits. All three have to be considered in the rental property purchase decision. Basing a purchase decision only on cash flow does not make good business sense if the property is declining in value and will be sold at a tax loss.
Rental property ownership is a SLOW road to wealth, but over the past 25 years, my 10% cash flow and property appreciation have made me a millionaire a couple times over. Tax benefits such as depreciation expense and tax deferred 1031 exchanges are just a bonus. The payday came for me when I retired at 49 years of age, my unearned income more than covers all my lifestyle costs, and my tenants keep "buying’ my properties for me.