How long can a Landlord keep your deposit?

Immediately.
Without discussion.

Contact the landlord-tenant organization in your area. Have them intervene on your behalf. get it in writing that the lease is cancelled and get your deposit back.

Thanks for the speedy answers! What do I do if the Landlord wont sign a Termination of Lease? Small claims? I really would hate to go that route, but will if I must.

Let me add: get pictures! If you can’t get the landlord to honor their agreement, small claims court is probably your only recourse.

Send a registered letter to the landlord with a return receipt. If you do not get a response, go to the courthouse and file in small claims. Many jurisdictions have legal limits to how long they can keep the deposit, if they fail to return the deposit in a timely manner the landlord may be liable for punitive damages as well.

See you on People’s Court!

What state are you in? These things vary by state.

Georgia

You should be able to find everything you need here
Have you told them you changed your mind and want your money back? You never did take possession, right?
It seems they didn’t hold up their end and should refund the money immediately.

Never took possesion, gave verbal and written notice, and its been over two week since the commencement of the lease. Thanks for the link!