I'm looking to do a flip in Atlanta and my issue with my first house that I purchased was dealing with bad contractors.

I also think it is a good idea to minimize your taxes now, while positioning yourself the best you can for the future (where everything is an unknown).It certainly would not be a bad thing to also use your retirement accounts to invest in real estate (as long as you are very careful to follow the rules- avoid self-dealing!). 

Real estate gets much harder if you have bad credit.

Do you think it is a bad idea to purchase near these vacant properties?

As @Rick Pozos mentioned, if it's listed, and it's been on the market a while, it's likely overpriced, has a major issue(s), or the surrounding area is so bad that it's driving buyers away. 

I am interested in the wholesale part of the real estate niche as I have bad credit and no money but I also am a law abiding citizen. 

This sounds easy and innocent enough but be careful because if this goes bad you can be in trouble because a judge could potentially see this held back as a lease option fee or owner financing down payment if he gets a smart lawyer .

It's bad that you didn't do anything with that knowledge.

What to look out for in determining potential neighborhoods (I am not local to the area and is curious on how "hot" neighborhoods started out and what signs to look out for)How bad can a bad investment be?

Ive heard good and bad things.