If this is their history, no special treatment.

This involves finding a reliable contractor, a property manager and a real estate agent who specializes in investment properties in the area.

My team at Vested Alaska specializes in multifamily in the Anchorage, Eagle River markets.

My section 8 tenants were the first tenants I had which possessed linkedin accounts and also had among the best FICOs compared to my tenants who were not on housing assistance.  

Should I put in special tubs/showers or just hand bars, and provide a shower seat? 

Consider specialized insurers like Nationwide, Farmers, or Liberty Mutual, which may offer policies tailored to multifamily rental properties.

I focus primarily on the upper valley but I can refer you to people who specializes in the Brownsville/SPI area.

I'm not a CPA (although I do know a great one that specializes in RE specifically) but you can run a cost segregation study to accelerate depreciation into the first year to help on taxes (although this is phasing out, but can still be powerful), and may help with your plan to do Roth conversions. 

It entitles them to possession.

These specialized companies, easily found online or here, will create your company's SD 401(k) plan.