Regional starting points
These county indices seed the comparison below. They cover different housing mixes; use comparable listings for your decision.
Typical home value
$296,846
Rock County, WI
· Zillow ZHVI
Zillow ZHVI county series · Retrieved . Coverage and method.
Typical monthly rent
$1,292 / month
Rock County, WI
· Zillow ZORI
Zillow ZORI county series · Retrieved . Coverage and method.
1 · Compare your options
What would each path cost?
Start with two homes that meet the same needs. A countywide home value and rent index can represent different sizes and property types.
Adjust tax and growth assumptions
Mortgage, growth and property tax rates are illustrative scenario assumptions. The starting 1.85% property-tax assumption is an illustrative budget, not a verified local rate. Use a complete annual tax estimate divided by purchase price. The $1,800 yearly insurance and $0 HOA defaults need actual quotes and dues. Check Wisconsin property costs
Starting scenario · 10 years · Before income taxes
Renting and investing finishes $180,332 ahead
This compares projected home equity after selling costs with invested cash. It assumes the cheaper housing path invests the entire monthly difference. Changing that behavior can change the answer.
Buying cash at closing
$68,275
Down payment + 3% closing costs; reserves extra
First year buying catches up
Not within 30 years
Annual checkpoints under these assumptions
Monthly budget in year one
Includes housing costs and utilities. Principal builds equity but still leaves your bank account.
Calculated from your inputs using the RentalCalcs model. See costs, source periods and exclusions. Dollar amounts are rounded after calculation.
Renting leaves $1,300 more per month to invest in year one.
Monthly cost breakdown
Scroll the table sideways if needed.
| Cost | Renting | Buying |
|---|---|---|
| Rent / mortgage P&I | $1,292 | $1,580 |
| Property tax | $0 | $458 |
| Insurance | $17 | $150 |
| PMI | $0 | $0 |
| Maintenance reserve | $0 | $371 |
| HOA dues | $0 | $0 |
| Utilities | $150 | $200 |
| Total | $1,459 | $2,759 |
What if you move sooner or stay longer?
Wealth at each exit date, including a home sale. These are nominal dollars and modeled outcomes, not market forecasts.
Scroll the table sideways if needed.
| Exit year | Rent + invest | Buy + sell |
|---|---|---|
| 3 | $134,935 | $70,340 |
| 5 | $186,419 | $94,776 |
| 10Your stay | $345,563 | $165,231 |
| 20 | $853,361 | $359,852 |
| 30 | $1,798,066 | $666,484 |
Take this scenario further
Change insurance, maintenance, transaction costs and other assumptions in the full calculator. All ten inputs above carry over.
Continue with these numbers →2 · Check the homes you are comparing
What matters for your decision in Janesville?
Read “improvements” correctly on the assessment
Janesville’s assessor FAQ explains that “improvements” includes buildings and other features already on the land; the label does not mean the seller recently renovated the home. Verify condition and repair costs independently. For a special assessment on the bill, the city directs questions to the clerk rather than the assessor.
Janesville assessment and special-assessment questions · Checked October 17, 2026. A source's tax year is separate from this review date; confirm the current property record.
Comparing another Wisconsin location? Keep financing assumptions consistent and replace the actual home costs in Madison or La Crosse. These are comparison options, not a ranking of places to live.
Property taxes after purchase
The 1.85% starting tax rate is an illustrative assumption, not a verified rate for this home. Look up the Janesville assessor and collector through the Wisconsin municipal assessor and clerk directory. The county housing index is separate from the city or town property-tax assessment.
Wisconsin taxes use municipal assessments and the applicable taxing districts. A mill rate applies per $1,000 of assessed value; it is not a percentage of your purchase price. The 2026 Wisconsin property-owner guide (pages 35–37) explains the bill and separate special charges.
Request a complete annual tax estimate for your ownership, then use annual taxes ÷ purchase price × 100. For example, $6,000 a year on a $400,000 purchase is 1.5%, or $500 a month. Leave Assessed Value at 100% in the full calculator after this conversion. Do not multiply by the municipal assessment ratio again.
Check Wisconsin tax-credit eligibility before carrying a seller's credits into your estimate. Credits already on a bill must not be deducted twice. Income-tax credits are separate and are not included in this before-tax comparison. Budget one-time assessments and old balances separately; the model's 2% yearly tax growth is an assumption, not a municipal revaluation forecast.
Condo dues and upcoming work
For a condo, enter the actual HOA dues and review the reserve study, meeting minutes and special assessments. The starting scenario uses $0 dues; that can understate a condo's cost.
Comparable space and location
Compare similar bedroom counts, commute needs, parking and outdoor space. A county home index and a county rent index do not describe a matched pair of homes.
Insurance quotes and cash reserves
The $1,800 yearly insurance default is not a Wisconsin quote. Wisconsin insurance guidance distinguishes flood coverage from a sewer-backup or sump-pump endorsement. Ask for property-specific coverage, premiums and deductibles. Enter the combined annual premiums in the full calculator and avoid duplicating coverage paid through HOA dues.
Try a three-year exit alongside your expected stay. Include moving costs, repairs and an emergency reserve in your real budget; the cash-at-closing figure does not include those reserves.
If you would rent out a room or unit, model a house hack separately so rental income and vacancy are explicit.
Looking for rent data or a rental investment?
For local rental research, browse Wisconsin rent estimates by city and ZIP; ZIP coverage differs from these county indices. To evaluate a property you would rent to someone else, calculate rental cash flow and returns.
3 · Understand the comparison
Sources and assumptions
- Home value reference · Zillow ZHVI
- Rock County, WI (county FIPS 55105; Zillow region 308). Observation: . All homes, mid-tier, smoothed, seasonally adjusted. Retrieved . Download the Zillow ZHVI county series (CSV).
- Monthly rent reference · Zillow ZORI
- Rock County, WI (county FIPS 55105; Zillow region 308). Observation: . All homes plus multifamily, smoothed, seasonally adjusted. Retrieved . Download the Zillow ZORI county series (CSV).
- How to use these indices
- Zillow's data definitions describe typical home values (ZHVI) and typical market rents (ZORI). They cover their respective housing stocks, not a matched pair of homes, Janesville city medians or an individual property quote. ZIP-level and listing-based sources use different coverage and may differ. Published source files may be revised after retrieval.
- Financing and ownership costs
- 30-year conventional loan; 3% purchase closing costs; $1,800 yearly home insurance, growing 3%; maintenance at 1.5% of purchase price, growing 2.5%; property taxes growing 2%; $200 monthly owner utilities. PMI is modeled below 20% down at a 0.5% annual rate, until the modeled loan-to-value reaches 80%. All are illustrative assumptions.
- Renting and investing
- $200 yearly renter insurance and $150 monthly utilities. Renting starts with the buyer's down payment and closing costs invested. The path with lower ongoing housing costs invests the difference. Security deposits, broker fees and moving costs are excluded from this comparison.
- Selling and tax treatment
- Selling costs total 7.5% of future home value, including commissions, closing costs and sale preparation. Buyer wealth is equity after selling costs plus invested savings; renter wealth is the investment balance. This comparison excludes income-tax deductions and taxes on investment gains. Dollars are not inflation-adjusted.
Use the full calculator to adjust the remaining costs and explore additional scenarios. Its optional paid report does not gate the free comparison.
Janesville rent vs buy questions
Does a lower monthly rent mean renting is better?
It helps your cash budget, but the wealth result also depends on what you invest, home value growth and when you move. Check both the monthly comparison and the exit-year table.
Why is there no universal Janesville break-even year?
The answer changes with price, rent, financing and investment returns. “Not within 30 years” describes the modeled window, not a claim that buying can never catch up. A first crossover also does not guarantee buying stays ahead.
Can I compare a cash purchase?
Yes. Set the down payment to 100%. The rent scenario then invests the purchase cash and closing costs, so the opportunity cost of paying cash remains in the comparison.