But is the main hurdle the permitting/zoning?

Also, please ensure your property is in a Zone where you can convert to the number of units you plan to create. 

What sort of red flags are here?

I know others do great with them, but it's not my comfort zone.  

I believe all the large redevelopment firms branching into areas through Opportunity Zones are the largest at-risk segment.

I'm currently eyeing a property potentially located in a flood zone.

Highly unlikely that your local zoning is going to allow apartments to be built on the bottom floor of a manufacturing building, @Brian Ellis.

It means nothing.Pay $5,000 to "Open the Door" and you have bought a black box of whatever the seller wants to provide (a paper application handed to you from a lender, a website address, etc...)When buying something like this and "Sales Fluff" is introduced into the conversation (vs. hard facts such as, a line of credit will be set up for $X 90 days after doing Y with Z lender, etc...) there is unusually a reason for the "Sales fluff".Ask for a copy of the contract and take the time to read it to see what you would actually get for your $5,000, and if the contract has "Sales fluff" in it--Buyer Beware.If there is no contract, or they balk at giving you an opportunity to read it (pressure you into signing now), it might not be such a good deal for you.And Sales fluff may be a red flag about other parts of the "Opportunity" also.Good Luck! 

What red flags or hidden traps should I be looking for?

My price range is anywhere between $80k to 150k.Any advice on which areas to zone in on and if you have any recommendations for lenders, agents, and contractors would be greatly appreciated!!