Meanwhile I have done some things right, I am saving 20% my income,  I am sending 14% to my employer's 401k, Became credit card debt free.

As it was during what would be normal work hours, landlord contacts my employer and accuses me of trying to collect a debt and threatening him on company time.

Hi @Pete Hathaway,As of loan funding and closing, there must be no indication that you have any intention to leave gainful employment.

The owner is 70 years old and has had the park for about 30 years.My 2cents - get it under contract with a comfortable DD (due diligence) cushion so you aren't wasting your time evaluating.They are currently getting $2450/month for rents, but has the ability to gross $4200/month if fully rented out at the $200/month rent.Are these market rates for comparable parks in the area, i.e. similar amenities, demographic, proximity to employment?

My wife is in Healthcare and there are plenty of opportunities for employment.

I cashed out of the stock market myself a few years back to start up my investment property portfolio, as I just grew tired of the unpredictable volatility game that comes with making money based on what everybody else does in the stock market aka out of my control.My money is doing so much more for me now in real estate, growing in more ways than one, under more my control with the ability to move it with more ease minus fees and penalties.Of course I'm not totally out of the stock market, as I still have money invested in some mutual funds through my employer and a HSA account.

Are there any that do everything like credit checks, background checks, eviction checks, employment checks, rental history, etc...?

This is why some advocate a rent discount (carrot) for early or on time payment, while still employing late fees (stick) for untimely payment.

I believe the Employer Identification Number that I was assigned by the IRS is still valid. 

If you're looking for a shift from a sellers market to a buyers market, it may be some time because employment seems healthy in most markets.