I would totally rent the property and STR/MTR the bonus suite.

i would say the most cost effective unit would be a garage with a bonus room, typically you can get half of the picth as footage in the truss so if you have a 40x60 garage you can get livable space above if (built in the truss) of 20x30=600 sq ft.the only down fall we have seen is stairs but most people dont mind if as long as your location, fit and finish are good

DepreciationThis is probably the best part, tax wise of owning a short-term rental property; How you write off business expenses for example consumable supplies for your rental business vs assets such as large machinery/cars/etc.Qualified Business Income(Purchase Price - Land Value) ➗ 27.5 years = Depreciation Tax Deduction(39 years for commercial properties)Bonus Depreciation: Since 2018, short-term rental owners have been allowed to deduct the full cost of property such as appliances and furniture all in one year using 100% bonus depreciation.

Bonus: If you can't update your house due to a tight wallet, your Airbnb needs to scream VALUE.

Just like anyone who thinks they bought a smoking deal because the appraisal came in lower than their purchase price and they think they have bonus equity that's not real either.   

Here is one proposal with taking 100% bonus depreciation this year in a 35% tax rate, ~33% effective rate.

I watch drops and pricing.Just like a regular seller the bank will go through a cycle to come to reality of the price needed to sell.In the day REO brokers would refer to being the lucky one on the carousel to get the property to sell.Usually these AM companies will list the REO drop a few prices and then re-assign.The property might be sold on the 3rd agent that gets it.When I watch the MLS I look for the updated BPO and by how much the bank is dropping.If they have had too big percentage price drops in 60 days I know it is time to hit them with a low offer.I don't want to wait until they drop too low as I will have competition to bid it up.Instead I want to know they will go lower and get it accepted.Every bank is different and some are really aggressive in wanting to sell.I have had bad AM's just kill deals and sometimes you can't do anything about it.Sometimes they are leaving the business and don't care,other times they already have the bonus for the month,and other times they are new and trying to make a name for themselves.We get this with BPO companies.Some new person comes on and flags everything for stupid stuff in quality control.Stuff that doesn't make sense.After a few weeks to a month of training the new QC reviewer learns the ropes and it gets better.

The IRS is not providing the depreciation to be generous.

In some cases you can also benefit by bonus depreciation via cost segregation.Step up in basis.  

Added bonus there is a hospital fairly close and my understanding is that people start accepting their residence programs in March.