I would price out the construction costs on both intentions and then make a decision and consider the maintenance costs of either type if you plan on keeping it long term.Its location and demand in that area should effect your decision too as well as site accessibility,  land research, the land contour plus how you might use any extra space or the current zoning allowance or the utilities that exist.

Great schools, great growth and the area is still fairly hot for construction and sales of existing.

That may have existed in the past, but not today for any attorney, trustee, or bank that wants to stay in business.

If the buyer defaults,  gets evicted,  do they sacrifice all their existing equity?   

If one of our customers wanted to add those to an existing job, we could probably fabricate and install it for around $2k to $4k depending on hardware selection.

You may not own the land so appreciation may be at a minimum or non existent. 

Sub2 means buying while leaving the existing financing in place & taking over the pmts. on that existing financing.

If so, then he can make you a 5% owner/member in the LLC (as long as this property is the only thing owned by the LLC).If not, then form an LLC to hold the property, where he is 95% owner and you are 5% owner.The LLC Operating Agreement will describe how distributions are paid.Note, giving you 5% of the existing asset could be a taxable event for you.

It has an existing rental history of 25k annual. 

@Shawn Gilbert Does Huntington Bank exist there?