pay a welder or buy a welder?

[djzphotos]

Im finally starting to get the ball rolling on my 65 c10. I need some advice on how difficult it would be for a first time welder to weld in some floor pans, rocker panel, and two exterior cab corners. I had found a mobile welder on craigslist who said he would come out and charge me $350 for an 8 hour days of work. Is there any way that someone could knock out that kind of a job in one day or would I be looking at a few more trips and a few more bucks. Depending on the cost for someone to do it, I was kind of thinking of just using that money to buy myself a welder and give it a go. If I could get some advice that would be awesome.

Thanks

The first two pictures are of the holes in the floors, the last pic is the passenger floor after I stripped the flooring and sanded out some of the rust.