I'm still figuring out how to improve the free marketing that works, for those of us with fewer units.

I don't serve the Tampa area, I'm only down here temporarily for the Air Force, but I am holding an investor meetup of my own. 

We bought for $133k and replaced the flooring, updated one of the kitchens - (a duplex) painted, and made a few other improvements.

Asking price is $159,000 and the house immediately next door sold for $599,000 but a few other houses in the neighborhood sold for much less but still above $159K.The house could definitely be rehabbed and improved both inside and the exteriorSo, here’s my question:Should I buy this house at $159K, rehab it, and hope it sells for around $599K?

You cannot change location, and you can only improve the house itself, not the neighbors. 

The improvements were financed through silent/private investors.

If you have truly made large improvements, then you have a chance to make it work.

Over the decades, "leaky air systems", bad plumbing, years of moisture causing rotting wood are "termite magnets" for older mobile homes.

Drop the price a little to get leads and improve the condition of the property to make sure it is clean and nice looking. 

Purchasing something that has room for improvements to increase value intrigues me as well.