The property in question is a mixed-use, with a ground floor commercial unit, and one residential unit upstairs. 

ya i cant see how you could possibly protect yourself with bee's wasps  I mean some of the nest are in the ground and very hard to detect..  

The older aged condo market is tough with so much new supply coming online and breaking ground. 

This house was very nice and clean (build later 1980) My tenant recently claimed there is mold on 1fl (it is like basement as there is no window, it is next to garage) When i see, the mold is not only one area but it seems widely spread on the ground floor (laundry room, wall, celiling etc) Since it is OOO investment, it is not easy to deal with mold issue.

We’ ve made some research and  spoke with couple of them however based on experience from investors on the ground we would like to hear from you and  any advice would be greatly appreciated. 

We source off-market deals, pair them with investors, and then hand hold through the rehab and city inspections when things are complete.We have existing contractor relationships and a team on the ground to keep tabs on things and keep you informed along the way. 

let me know if you have any questions in regards to bridge, fix and flip, ground up construction and DSCR 

Market data research and boots on the ground are the unbeatable tools to find these areas and invest heavily there.

and I'm gearing up to start the rehab soon.I invest remotely but will be visiting Detroit in a few weeks to spend some time on the ground.

You should engage a property manager though for this property and if you think there are grounds for eviction I'd try to move on those with an attorney ASAP.