check your state regs... get whatever license you need to be a HML... maybe you don't need one for non owner occ commercial purpose loans.. many states you do not need any licnese for this activity.Then take your cash and credit score to a bank.. put up the 200k for a 5 to 1 credit facility to back fill hard money loans... make loans at 15 to 20% which is common in TN  that's what I have always gotten in Memphis... borrow from said bank at 5 to 6%  make the delta.that's 100k on the 1 million credit facility a year and 30k on your 200k.. that will get you started  then.. bring in private investors and fund deals for them once you have done it yourself and shown that you know what your doing... let all the others try to flip houses etc. while you collect your payments... and then you can leverage it up... once you get to about 5 million you have a real business.YOu bring in other equity partners for your cash component they can be passive or with you.

Currently collecting rent from a duplex (2 checks monthly) and a self-storage facility (42 checks monthly).

How do rents collected differ from total rents for the facility?

The regulations set out four assessment factors to assist entities in determining whether miniature horses can be accommodated in their facility.

Or to medical facilities?  

Tenant shall not permit any person in or about the premises to deface damage or remove any part of the structure of the premises or the facilities, equipment or appurtenances thereto, nor personally do such things.Tenant shall be responsible for all expenses in connection with any repairs caused by tenant’s failure to comply with the foregoing conditions.

Also I'd not over think it; Apartments are noisy, and as long as there are separate entrances/laundry facilities it shouldn't be too much trouble as long as you can figure out how to handle the separate utility billing to the tenants.  

Some locales will also have additional fees and charges to pay for schools, medical facilities or other public projects - and sometimes those fees pay for golf club memberships or new personal vehicles for people in county/city government (it's not cool but it happens, and it's perfectly legal in many cases).

That said, you usually don't go wrong looking in stable neighborhoods without a lot of demographic shifts, reasonably close to shopping & employment, and in communities with at least a few "recession-proof" industries - military bases, medical facilities, universities, etc.

Maybe you could recommend him a treatment facility or something...I suppose my whole point is, be careful bringing personal matters into a business transaction.