They should also re establish a new exit strategy, performance metrics, establish new expectations. 

The heights recently underwent change in zoning, so investors/developers are beginning to pay more per lot to build.

Tutorials  emphasize the need to do due diligence on all the following:--check for taxes and liens against the property--find out which taxes and liens, if any, will remain attached to the property--make sure it is a buildable lot--to do above, you need to establish how the lot is classified for code purposes, and access the lot specifications, minimums the lot must meet for construction to be allowed--you further need to find out what its sewage situation is because 1) municipalities have different lot minimum specification for lots with public sewage and lots with septic; and 2) if the lot will require the construction of a septic tank, you need to take that into account in your decision.

Should I establish an LLC and close in it at this stage of my investing journey?

I would recommend that you first Identify a strategy and make sure that the market you choose that aligns with it then establish your Core 4 Real Estate Team. 

So would potential tenants look at that and think they wouldn't want to rent the property becasue of that, even with it being in a "nicer well established" neighborhood?

Especially if they are established tenants.

You may also try to stop by your local Bank of the West branch - better than trying to establish a relationship by phone - to see if they offer investment HELOCs in TN.

Like buyers, sellers have a lot to consider, especially if they are getting bombarded with showings and offers.

Identify your investment goals first, then choose a market that aligns with it and establish your Core 4 Real Estate Team.