As you are finding out, it is so local that the next door building effects your investment. 

Small investor with 5 properties (10 doors) and made a 2025 goal to start using more of the features of BP. 

They can't assess all the subjective data like overall layout, view from the living room window, the dogs next door that bark all day, the width of doorways, size of individual rooms, quality of kitchen cabinets and appliances, etc.The best thing to do is study your market regularly.

I'm in a team who does these deals and we have a team of "door knockers" who go back weekly till the auction, they file bankruptcy which only delays 3+/- months 100% chance that the lender will as that their mortgage is removed from the bankruptcy they file NOD yet again.   

A buddy of mine up in Omaha once inherited a tenant who refused to let inspectors through the door.. ended up pushing back renovations for a month and racking up costs like you wouldn’t believe.

Pack their items, change front door locks and give new locks to other tenants.

I own 12-doors in Detroit and 3 of those are rented to section 8 tenants.The best areas for S8 tend to be C Class neighborhoods.

A little background about me, I have just over 200 doors in my current portfolio and our company manages just over 250 doors for third party investors in addition to those. 

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.

I think your demographic might be more hotel people rather than families.I would also still go with smart locks on every door.