Since your realtor said it's part of an estate that usually means that more properties are selling unless he was just saying this one house is available because someone died.

When looking at other STR listings in Detroit I see that they are available way more than 90 days per year.

Every system you try will have flaws, or you may salivate over a feature that appears in other software.Some familiar names are mentioned frequently: Stessa, Apartments.com, RentRedi, TenantCloud, Innago, RentManager, Avail, Rentec Direct, Doorloop, etc.I recommend conducting thorough research on each app online to understand their offerings, pricing, etc.

Sometimes back of the envelope underwriting is ok, but not enough information is available here to suggest this is a $520k-$580k opportunity.  

I have a home available for rent and have a prospective tenant that says he has a pitbull as a service animal. 

This not only creates financial strain for landlords but also results in fewer rental units being available, exacerbating housing shortages for new tenants.Another major challenge is the backlog at the Landlord and Tenant Board (LTB).

I have considered that a 3 year lookback might be insufficient for a complete analysis; but it's what's available right now.

However, the real education is at the Broker/Owner retreat, available only for Broker/Owners.

Quote from @Jamie Hora: The question you pose in the title, "Is a rezone required if availability study can support more density". 

Every system you try will have flaws, or you may salivate over a feature that appears in other software.Some familiar names are mentioned frequently: Stessa, Apartments.com, RentRedi, TenantCloud, Innago, RentManager, Avail, Rentec Direct, Doorloop, etc.I recommend conducting thorough research on each app online to understand their offerings, pricing, etc.