A couple of things to consider for the homeowner, increases in property taxes and insurance but also the taxable revenue from the rental and its impact on personal taxes you will have to pay. And then there is resale value for a property that is locked into multi year agreement.
Not an issue in the bay area
>the taxable revenue from the rental and its impact on personal taxes
Progressive income taxation should make this moot. Also many expenses are likely tax-deductible. Combined with FHA terms, mortgage interest deduction, etc. and this is actually rather tax-advantaged over regular rentals