Here are some great links and references that helped me:
1. A great reference for you is the Georgia Landlord Tenant Handbook (http://www.dca.state.ga.us/housing/HousingDevelopment/programs/downloads/Georgia_Landlord_Tenant_Handbook.pdf)
2. Georgia renter legal advice (http://legalaid-ga.org/documents/4068912007%20repairs%20final.pdf?stateabbrev=/GA/)
3. The Rental Protection Agency: for $35 you can file a complaint against your landlord which will go on his public record and be assigned your own RPA agent to negotiate between you and your landlord… I used this when dealing with my mold issues, and with the “rush” service, an agreement was tragedy in 3 days, my lease broken, and certified documents of the process included to being to court for reimbursement of damaged property (http://www.rentalprotectionagency.com/complaint_center.php)
4. Finally a very simple step-by-step guide on the information needed and how to break your lease due to mold: (http://www.ehow.com/m/how_6367203_break-apartment-lease-due-mold.html)

Your two main goals should be determining the type of mold you have (Black Mold is the big one for getting you out of your lease, since it is very hazardous to your health), and demonstrating Landlord negligence in repairs… a four month delay is DEFINITELY negligence (this will allow you to be reimbursed for all your damaged property and belongings).

For mold testing, contact your local health department, and they will send out an expert. Make sure the type(s) of mold are documented (especially Black Mold!!) and the ratio of mold parts per air. Have this documented, and make sure you have a copy for yourself, your landlord, and an attorney/the court (and/or to put up on Rental Protection Agency to further document your case and increase your evidence when it is compiled for court). Also take as many pictures of the mold as you can (try to show every surface affected by the mold from several angles); if possible, also include a rough estimate of the size of the moldy area on each surface as well along with your own written description of the appearance of the mold, circumstances that it developed under, and the date you first noticed it. Document any and all adverse health effects you and your family are experiencing; remember if it is Black Mold, a doctor appointment is a must. Make copies of the doctor’s prognosis/diagnosis for yourself, landlord, attorney, etc. as well.

Result: If Black Mold is present, your residence will be deemed uninhabitable and your lease will be broken.

For negligence, it’s all about keeping records and keeping more records. Try to date (if you don’t know the exact date, approximate) each time you made a complaint to your landlord, the date he responded to the complaint, the date repairs were made to fix the complaint, the date repairs were completed (both initial repairs and the repair that actually WORKED). This is all about developing a timeline to prove your landlord was not responding to your problems in a timely fashion, therefore demonstrating neglect in his duties as a landlord. Also chronicle (in writing), the results of the repairs and any resulting damage from it. Make sure to mention if you were told any and all necessary information for the repairs prior to their beginning (for you, this would be not being notified that your home would be uninhabitable during the roof repairs). Last, approximate the value of your personal property damaged (if you can do it by individual item or provide any receipts or credit card statements from the time of purchasing your now ruined item, include this). Also include bills for any dry-cleaning, laundromat or repair services used to fix or clean any of your damaged goods (this includes any and all articles of clothing, etc. that were moldy or exposed to the mold even if it is not visible).
NOTE: you can keep these cleaning receipts for the overall packet you will take to court for reimbursement OR you can deduct the cost from the amount you pay in next month’s (or the month after that if the total is high enough) rent. Just make sure to notify your landlord that you are proceeding this way (it is your right as a renter, don’t let him stop you), and make sure this correspondence is in WRITING (ie. An actual letter, not telephone or email).
THIS IS IMPORTANT! Try to make all correspondences between yourself and your landlord in writing through the mail. Ask him to do the same. This proves that he received your message. Make sure to keep copies of all correspondences. Even if there is an emergency and a phone call is necessary, write a letter pertaining to the issue immediately after.

Result: Negligence is definitely evident in your situation, just make sure you document it as thoroughly and accurately as possible so that it doesn’t come down to a “your word vs. their (landlord) word” situation. If landlord is deemed negligent, you should receive 100% reimbursement on all your damaged personal belongings.

Hope this helps!

PS. Even if you decide not to use the $35 service from Rental Protection Agency, you should still file a report against your landlord on the site to go on their public record (this service is free)… Hopefully then other people won’t wind up experiencing what you have gone through… Not to mention it is fairly discrediting your landlord’s reputation.