Messed up 91 Accord

I have a 91 Accord, and I have a problem with body work. The left side (around and through the fuel door) has a big gash down the side. I just started pulling out the dent and putting bondo in it, but I'm noticing that the shape is hard to get... above the fuel door, the body goes to an angle and that part is ripped/gashed. I have no idea how to fix it, it goes from the tail light, about 4 ft. forward. At this point, I believe I have 3 Options:

1. Keep layering body filler until it comes out straight
2. Weld in new metal to repair the shape
3. BODY SHOP (I got an estimate of 800-1000 for whole car w/paint)

BTW, I DID NOT DO THE BODY DAMAGE!!! and... I am an amateur (obviously) when it comes to body work, so plz take that into consideration

seems very cheap, it was 3grand to repaint my bros bmw, and that was so that it looks like new, but um.......i would let the body shop do it, and is a good body shop, or a small one?that seems really cheap