Bonneville County

Bonneville County sits firmly on the appreciation side of the cash-flow versus appreciation spectrum, and the numbers make that positioning hard to argue with. At a median home price of $400,373 and median rent of $1,440, the gross rent-to-price ratio comes in at 0.43%, annualized to roughly 4.3%. That's thin. The model cap rate of 2.81% confirms it: you are not buying yield here, you are buying a bet on continued price growth. Year-over-year appreciation of 1.55% is positive but modest, and the affordability index of 44 signals that prices have outrun local incomes enough to compress both renter purchasing power and the pool of future buyers. The cash-on-cash return at current financing of negative 15.14%, with an estimated monthly shortfall of $1,162 on a 20% down purchase at 6.85%, means this market punishes leveraged buyers who need the property to service itself. At a national percentile of 19 out of 1,000 counties tracked, Bonneville ranks in the bottom fifth for overall investment attractiveness on a composite basis.

The buyer this market suits is someone acquiring with substantial equity, a long time horizon, or both. A pure cash-flow investor running standard leverage should pass. At 80% LTV, the monthly mortgage alone is $2,099 against $1,440 in rent, and even before operating expenses the deal is underwater. A cash buyer or a buyer putting 40% or more down can get expenses to pencil closer to break-even and hold for appreciation, but that requires patient capital tolerating years of flat or negative distributions. An appreciation-focused buyer who believes Idaho's broader growth story has runway is the natural fit here. A value-add operator would need to find assets priced meaningfully below the $400,373 median and push rents above the $1,440 median, which is possible in pockets but difficult to systematize across a market with a 66 appreciation score and a 35 cash-flow score; the market rewards the former, not the latter.

The property tax and insurance picture provides a genuine tailwind worth acknowledging. Idaho's state-average effective property tax rate is 0.69%, flagged as low, and the blended annual insurance cost runs approximately $761 at a 0.19% rate. Together, monthly tax and insurance on a $400,373 purchase comes to roughly $294, which is materially lower than what investors underwriting comparable price points in Texas, Illinois, or New Jersey would face. That said, the honest caveat embedded in the data is worth repeating: this is a state-average effective rate sourced from Tax Foundation 2024 estimates, and actual county and township assessments in Bonneville can differ. Before closing, pull the county assessor's current mill levy and run your own figure. The low-rate designation is a reasonable signal, but it should not go unverified in your underwrite.

The primary risk in Bonneville is concentration. The county seat, Idaho Falls, is a regional service hub, and the local economy has historically benefited from federal presence at the Idaho National Laboratory (INL) roughly 50 miles northwest in Butte County. That federal anchor drives meaningful professional and technical employment in the broader eastern Idaho region and supports above-average household incomes relative to rural Idaho norms, which in turn underpins rent stability better than the raw rent-to-price ratio might suggest. But a market of 124,490 people with a single dominant economic anchor carries concentration risk; a policy shift affecting INL funding or mission would have an outsized effect on professional rental demand. Regulatory risk is currently low by Idaho standards, as the state has no rent control framework and landlord-tenant law is generally favorable, but that is a condition, not a guarantee.

Among the neighbors provided, Bonneville's closest direct competitor for an investor's attention is Elmore County, which at a $355,620 median price and $1,584 median rent produces a gross rent-to-price ratio of 5.35%, compared to Bonneville's 4.32%. That gap is meaningful at scale. Elmore also carries an overall score of 50 versus Bonneville's 48 and a lower entry price by roughly $45,000. Bear Lake County comes in at $391,387 with a slightly higher overall score of 49 but no rent data provided in this set, making it harder to underwrite blind. Boundary and Owyhee counties both score at or below Bonneville with higher median prices, making them difficult to prefer on either a cash-flow or value basis without additional data. An investor should choose Bonneville over its neighbors specifically when the thesis is regional growth tied to Idaho Falls's role as eastern Idaho's commercial and medical center, or when proximity to the INL employment corridor is the explicit demand driver. If cash-flow is the priority, Elmore's 5.35% gross yield warrants a serious look first.