IPhone 4 wont charge

My IPhone 4 starting having charging problems like 3 days ago. I did a chat with Apple and they said that I my charging port is likely dirty and to clean it with a toothbrush and some rubbing alcohol and it will likely fix the problem. I did it last night and it worked somewhat, never got my phone fully charge, but up to like 80% and was able to get all my pictures and videos off my phone. I am using 2 apple certified chargers but now today it wont charge again.

I have been waiting for the Ihpone 6 for 4 years so I plan on getting it in eventually, but I was hoping to wait until after the first price drop as the phone are usually insanely expensive when they first come out. But now I can barely use my phone and it is not only my personal phone but my work phone. Obviously I am not going to pay to have it "repaired", as apple says that will be like $170 and I will have to send my phone out which I need for work and personal use. Any suggestions on how to fix this? I will try the brush and rubbing alcohol again tonight, but if it didn't totally fix it before not sure it will now, but I have had this phone for like 4 1/2 years and never a problem and now out of the blue it is barely usable.