How do you overcome the objection from a landlord that a STR would create more problems for the owners than a regular rental would. i.e.- there would be more traffic and there is a permit to obtain from the County.  

Albeit, the grass will require regular maintenance but it is a quick inexpensive fix.

So I want to see that they’re still getting paid this money, and the actual break down on the check stub of how much they get paid per hour, how much of it was overtime, whether they regularly earn overtime, any garnishments or involuntary deductions, year-to-date pay, etc.

There aren't really any mobile home parks close that I know of.But there is this neighborhood with 5000 sq ft lots that have MH and some older built regular homes.  

Do you find your experience using this strategy better than regular SFH 

Modular houses are not the same as a regular one.

Which means self employment tax.The residential treatment facility might be considered residential investment property or not depending on the level of care, regularity of assistance, and if the majority of tenants have long or short terms stays.A more careful analysis is needed for both of these situations to determine the taxable nature of these activities.

I am trying to decide whether I want to do a regular rental or owner finance the trailer and rent out the space.

@Matt Bonestroo it’s more of a how to get my license, is it the same as a regular car dealer license or is it a more specific license?

I also see good investors picking up enough deals regularly to make a very good living on.