Interesting discussion on landlords and rent increases.
From personal history.... since COVID we haven't put our rent up. But, when some our expenses dropped (by changing the mortgage to interest only and then once interest rates have fallen) others have risen, so no, we haven't reduced the rent.
Also, the only expense that can reduce is the interest on the mortgage.... repairs and maintenance varies from year to year with sometimes being more than we budgeted and sometimes less. Rates, fixed water fees, insurance keep going up.
If the interest deductibility restrictions had remained in place, in the future, we would have considered that, along with other increased expenses, as to how much we'd raise the rent. BUT, that's also in line with what we think the tenants can afford. We've finally got some good tenants so don't charge them market rent as they look after the property, have never missed a payment and haven't caused us issues.
When we brought the property, it was actually with the intention of shifting into it ourselves when we'd retired and transferring the balance of the mortgage on the existing family home and renting that out. Because our family home didn't have a mortgage on it, the equity we had in it meant we were able to borrow 100% of the purchase price but that also means we pay towards the expenses/mortgage on the property. If we instead charge the tenants for all the expenses, the rent they pay would need to increase by over 35% from what they currently pay. We see the amount we pay into the rental property each month as a form of "compulsory saving" as it's reducing the amount owed to the bank.
When we do retire, we'd have paid back enough of the mortgage, that we'd refinance the property back to a 30 year loan but the rent would then be able to cover all the expenses so we wouldn't have to contribute to it.
BTW, I've also run my own business for 35 years and have more money in KiwiSaver and other managed funds plus directly owned shares than the equity in the rental. We see it as another form of investment.... certainly not our only one.