The mortgage would stay under the seller's name.The buyer could then rent out the unit, renovate, etc. to increase cash flow or make more money.But aside from a possible "due on clause" being called by the mortgage company, what's the benefit to the seller?

A more intrusive approach would be to Google the owner name and see if you can find relatives and skip trace and call them.

Plus, compared to other parts of Florida, the Panhandle is still relatively affordable, making it a great option for first-time investors or those looking to diversify their portfolio.Another huge perk is Florida’s no state income tax and landlord-friendly laws, which make it easier to manage and profit from rental properties.

To simplify the existing lease I thought about asking the tenant if they would be ok modifying the addendums to get rid of the resident benefit package and the building protection plan. 

One of my early properties barely broke even, but after a couple of years, rent hikes and expense optimization turned it into a strong performer.For cash flow benchmarks, I usually aim for $200-$300 per unit, but your situation.. house hacking.. offers unique benefits like reduced living expenses and quicker equity buildup.

This amounts to lost opportunity because if you had purchased RE, at the closing it can start producing return. 5) ADUs detract from the existing structure whether this is privacy, a garage, or just yard space. 6) this is related to number 1, but there are many more buyers looking to purchase homes for their family than there are RE investors looking to purchase small unit count properties.

For example, for any lease-related activities (negotiating terms/pricing, signing lease, etc.) could I just have a real estate attorney on retainer to do these activities? 

Sorry, it is not simple.Also, not just any "business-related" hours count.

that we’ve learned in our 24 years, managing almost 700 doors across the Metro Detroit area, including almost 100 S8 leases:Class A Properties:Cashflow vs Appreciation: Typically, 3-5 years for positive cashflow, but you get highest relative rent & value appreciation.Vacancy Est: Historically 10%, 5% the more recent norm.Tenant Pool: Majority will have FICO scores of 680+ (roughly 5% probability of default), zero evictions in last 7 years.Class B Properties:Cashflow vs Appreciation: Typically, decent amount of relative rent & value appreciation.Vacancy Est: Historically 10%, 5% should be applied only if proper research done to support.Tenant Pool: Majority will have FICO scores of 620-680 (around 10% probability of default), some blemishes, but should have no evictions in last 5 yearsClass C Properties:Cashflow vs Appreciation: Typically, high cashflow and at the lower end of relative rent & value appreciation.

Other advice, especially that pertaining to tax benefits, is also highly appreciated!