that sounds like alot of rust and some of those areas can be fiddley... as a panelbeater i would say dont expect much change out of 5 grand (without seeing it) if you want the job done properly. anyone could weld it in but you are paying for knowl;edge too. what the metals do when welded together, water catachment points etc... if you want to have a go go for it! you will be all the wiser for the experience. an arc is out of the question. mig is the way to go as oxy will produce too much heat and distord the metal.. anything bigger than a 130. i have a cig 130 fan cooled (is a must) at home and used to for 12 years and it still welds great.

hope this helps