Buying tax liens over the counter in Georgia

[Marc Bazemore]

Greetings , i'm a wholesaler ,fix and flip investor in the Atlanta market  i was needing some help with buying tax liens over the counter 

- Where do you go to buy them?
- once purchased is there a redeemable period the owner could get the rights to their property back?

-what pitfalls should i look for that is not on the lawyer side of the closing due diligence besides the property its self being 

 bad ? 

 Thanks !