MHP are great low liability (you're just renting the dirt) but then you have a completely different tenant than apartments or single family homes.

Long story short I decided to pay an exterminator to take liability off of me.

However as you said, as an investor I would not go in for equity and only do this as debt for the sheer aspect of liability. 

I think the "ideal" seller who benefits the most from this type of transaction is one who has a low cost basis in the property and low mortgage liability, and anticipates a substantial tax liability from capital gains and/or other income.  

The insurance you buy will basically cover damage to the interior of the unit as well as liability, though it should certainly be cheaper than normal because it won't need to include damage to things like the building's roof/siding/etc.Also, if you haven't already, make sure the condo board allows owners to rent out their unit. 

Insurance and Liability are always my first concern, pass it by your insurance agent first for their suggestion.  

yes, although I am a qualified intermediary, I am also an avid real estate investor and I had a self storage facility that I had purchased and about three years later I had grown the facility to its filled potential and it was ready to sell but I had a 7 figure gain and that, coupled some depreciation recapture (especially since I had taken advantage of some bonus depreciation the first couple of years, I wanted to defer the appropriate 350,000 tax liability at all cost.  

I don't really look at which one is the "most profitable" in and of itself but rather which produces the most passive income with the least amount of liability and daily involvement.The lending business is great because I do not use any of my own funds, I am in the safest part of the equity stack, the investor takes all the risk with the rehab, and does all the work. 

Completely agree with @Ali Boone here, your own home is more of a liability in my mind.

If a seller has equity in the property and has been unable to sell it, ask him to get a loan on it, let all parties know that once the property is refinanced, you are going to assume the mortgage with a release of liability for the owner.