Properties are sitting on market for a bit longer now that supply is slowly creeping back up. 50 days isn't too terrible compared to the greater PHX area. 

The cost to maintain them probably wouldn’t be exactly 8x as compared to the single 8-unit, but it sure as hell isn’t a 1-to-1 ratio either. 

Focusing on what you can control, like consistent effort, really sets the foundation for success.

There are plenty of deals in Philly on and off-market from wholesalers, who are pretty decent in Philly compared to other places.You will need to get your GC license here and learn the permitting process and necessity here as well.

What happens to the 'comparable value' if the area is uninhabitable or a community that won't return for years? 

What I have seen in the research is to find a property you are interested in and compare to other comps in the same neighborhood.

The most useful switch I made was from a vendor who kept insisting the water was fine (it wasn't and no, the chemicals didn't just need more time) to a true pro who doesn't gouge us for maintenance and does a consistently great job.

Throw in that you can dramatically increase the value of the property once you show consistent rent rolls much higher than when the space was used for LTR, and you have a big win. 

Multifamily properties do require more management overall and typically appeal to a smaller, investor-focused buyer pool.At my stage, I prefer small MFH over anything else because of the stronger cash flow, scalability, and the more forgiving capex compared to larger MFH, but the best option depends on your goals and strategy. 

I know you mentioned other units are listed comparably but asking price is not the same as rented price.