Any ideas, direction, or help would be appreciated. 

Any suggestions would be appreciated!

If you have any suggestions I would really appreciate it!

The area is rapidly changing/appreciating and will continue to do so. - You can absolutely manage 2 units yourself.

Original plan was to build 3-5 years down the road, but now with the lot fully paid off and significantly appreciated, I would like to use this equity to kickstart real estate investing into cash flowing properties.

Really appreciate the breakdown of this process.  

If you want cash flow in NJ, it's usually going to be in a C or lower area with little appreciation potential.

Thank you, and I appreciate all input!

If you are selling two properties that have appreciated (or have taken significant depreciation), then a 1031 exchange is almost certainly a good route since you're looking to reinvest. 

Call them after you issue the notice and let them know that you appreciated their stay, but that for a variety of factors that are cited in the notice you need to move in a different direction.None of this is personal for you, this is just about your asset; act accordingly.