Underwriting a Lake Murray rental: cap rate, cash flow and the costs people forget

A rental works or it doesn't on paper long before it works in life. Here is how I look at one, in plain language.

Start with realistic income

Use rent you can document from comparable units, not the top of the range. For a short-term rental on the lake, confirm the parcel's county and HOA rules allow it before you count a single night, then use seasonal occupancy that accounts for the lake being quiet from November to March.

The four expenses people forget

Vacancy, usually five to eight percent of rent. Maintenance and capital reserves, often another eight to ten percent, more on older homes and anything with a dock. Management, if you're not local, typically eight to ten percent for long-term and much more for short-term. And the lake-specific items: dock maintenance, shoreline erosion, higher insurance. Leave these out and every property looks good.

Three numbers that tell the story

Net operating income is rent minus every operating expense, before the mortgage. Cap rate is that income divided by the price; it lets you compare properties regardless of financing. Cash-on-cash return is what's left after the mortgage, divided by the cash you actually put in. Lenders also look at whether net operating income comfortably covers the payment; most want a cushion of twenty percent or more.

What I add

Real comparable rents and sales, the actual expense history where a seller has it, the rules on the specific parcel, and an honest read on whether the property will lease easily. I'd rather talk you out of a mediocre deal than into one; the next one is usually better. The calculator in the Investor Market will get you started; a conversation with me finishes the job.

General information, not advice for your specific situation. I'll tell you when a question needs a lawyer, a CPA or a lender, and point you to a good one.