The analysis guide covers running NOI, cap rate, and cash-on-cash before you buy. This is what happens to those numbers once you actually own the thing, the ongoing, recurring costs that don’t show up in a single month’s cash flow projection but absolutely show up over a year of owning a rental property.
Short version: a reasonable rough filter is that roughly 50% of gross rental income goes to real operating costs, vacancy, maintenance, capital expenditure reserves, management, insurance, taxes, before the mortgage ever enters the picture. Vacancy between tenants, turnover costs to re-rent a unit, and capital expenditure reserves for the roof and HVAC nobody’s thinking about yet are all real, recurring costs, not occasional surprises. And the single largest number in this whole guide: a bad tenant placement that ends in eviction can run $15,000-30,000 in total exposure once lost rent is factored in, which is exactly why the next guide in this series, on tenant screening, matters as much as it does.
The 50% Rule: A Rough Filter, Not a Precise Number
A commonly used shortcut in the industry: expect roughly half of gross rental income to go toward real operating costs, all of it, vacancy, routine maintenance, capital expenditure reserves, management fees if you use them, insurance, property taxes, bookkeeping, and the value of your own time. The other half covers the mortgage and whatever cash flow is actually left over.
This is a filter, not a final underwrite, newer properties tend to beat it, older ones tend to come in worse, and a market with fast-growing rents can outrun it over time. But if a property doesn’t pencil out even at the 50% assumption, that’s a real signal worth taking seriously, not a reason to lower the assumption until the deal looks better on paper.
Vacancy: The Gap Between Tenants Costs More Than It Looks Like
The national rental vacancy rate sat around 7.3% in the second quarter of 2026, and a reasonable budgeting assumption for a single property is close to that, roughly 8% of annual rent, or about one month a year. On a $1,500-a-month rental, a six-week gap during a rough turnover year works out to roughly $1,500 in lost rent, real money that a single month’s cash flow projection doesn’t show you until it actually happens.
Turnover: What It Actually Costs to Re-Rent a Unit
Beyond the lost rent itself, actually turning a unit between tenants, cleaning, painting, minor repairs, sometimes a bit more, commonly runs $2,000-4,000 per turnover, on top of the three to six weeks of vacancy that usually comes with it. A property with high tenant turnover isn’t just losing rent more often, it’s absorbing this cost more often too, which is worth factoring into how you think about tenant retention, not just tenant placement.
Capital Expenditure Reserves: The Roof You’re Not Thinking About Yet
This is the cost category first-time landlords underestimate most consistently, because nothing forces you to think about it until a major system actually fails. Two practical ways to budget for it: roughly 1% of the property’s value annually, or about 5% of monthly rent set aside specifically for capital expenditures, separate from routine maintenance. Either approach is meant to build a real reserve for the roof, the HVAC system, the water heater, and major appliances, the stuff that doesn’t break every year but absolutely will eventually, and tends to cost thousands of dollars at once when it does.
Skipping this reserve doesn’t make the cost go away, it just means the eventual repair shows up as an unplanned emergency instead of a line item you already budgeted for, usually at the worst possible time and often at a higher cost since deferred maintenance tends to compound into bigger problems the longer it sits.
The Eviction Number Nobody Budgets For
This is the largest single number in this entire guide, and it’s worth sitting with. The direct legal and court costs of an eviction typically run $3,000-5,000 on their own, with the average landlord reporting something closer to $3,500 and a real range extending up to $10,000 depending on the state and how contested the case gets. Add the lost rent during a process that can run anywhere from three to four weeks at the very minimum, and often several months longer depending on the jurisdiction’s timeline, and total exposure on a single bad tenant placement commonly lands somewhere in the $15,000-30,000 range.
Rigorous tenant screening, covered in the next guide, is the primary lever for reducing how often this happens, it doesn’t eliminate the risk entirely, which is exactly why it’s worth carrying a real reserve for this specific possibility rather than assuming it won’t happen to you. Worth knowing too: a portion of rent backed by a government housing authority, Section 8 being the most common example, arrives with a different risk profile than an unassisted tenant’s full rent, one factor some landlords weigh specifically against this exposure.
Rising Fixed Costs Most First-Time Buyers Don’t Anticipate
Two costs worth planning for as trending upward, not flat. Insurance premiums have been climbing meaningfully in a lot of markets, covered in more detail in the landlord insurance guide, particularly in states with real weather or climate exposure. And in many jurisdictions, a property’s tax assessment can reset at the time of sale, meaning the tax bill you inherit as a new buyer isn’t necessarily what the previous owner was actually paying, worth confirming directly with the local assessor’s office rather than assuming the current listing’s tax figure carries forward unchanged.
Putting the Real Numbers Together
Run the rental property calculator with genuinely conservative reserve assumptions, real vacancy, real maintenance, a real capital expenditure reserve, not the optimistic defaults a listing site might use to make a deal look better than it is. If the numbers still work with all of this built in, that’s a property worth taking seriously. If they only work by skipping half of what’s actually in this guide, that’s useful information too, just not the version most people want to hear before they’re already emotionally attached to a specific deal.
The full checklist includes a dedicated phase for budgeting these real costs before you close, not after.
Frequently Asked Questions
A rough industry shortcut suggesting roughly half of gross rental income goes toward real operating costs, vacancy, maintenance, capital expenditure reserves, management, insurance, and taxes, with the other half covering the mortgage and remaining cash flow. It’s a quick filter, not a precise underwriting tool, run the actual numbers before committing to a specific property.
A reasonable assumption is around 8% of annual rent, or roughly one month per year, close to the national rental vacancy rate. On a $1,500-a-month rental, that works out to real, budgetable lost income, not just an occasional bad-luck event.
Commonly $2,000-4,000 per turnover for cleaning, painting, and minor repairs, plus three to six weeks of vacancy during that period. High tenant turnover compounds this cost, which is part of why tenant retention matters financially, not just operationally.
Two practical approaches: roughly 1% of the property’s value annually, or about 5% of monthly rent set aside specifically for major system replacements like the roof, HVAC, and water heater, separate from routine maintenance.
Direct legal and court costs typically run $3,000-5,000, averaging around $3,500, with a range up to $10,000. Once lost rent during the process is included, often three to four weeks at minimum and sometimes several months depending on the state, total exposure on a single bad placement commonly reaches $15,000-30,000.
In many jurisdictions, a property’s tax assessment can reset at the time of sale, meaning a new owner’s tax bill isn’t necessarily what the previous owner was paying. Worth confirming the actual post-sale assessment with the local assessor’s office rather than assuming the listing’s current tax figure will carry forward.
No, generally the opposite. Skipping a capital expenditure reserve doesn’t eliminate the eventual cost, it just turns a planned expense into an unplanned emergency, often at a higher cost since deferred maintenance tends to compound into larger problems the longer it goes unaddressed.
Sources
- https://www.evernest.co/blog/the-8-hidden-costs-first-time-landlords-always-miss
- https://www.baselane.com/resources/tenant-turnover-statistics
- https://www.baselane.com/resources/best-capital-reserve-account-rental-real-estate
- https://www.outsourcedbookeeping.com/real-estate-cash-flow-the-complete-2026-guide/