What to do about tricky crawl space?

[Matthew Scott]

I am trying to decide what to do about this crawl space at the bottom of a duplex. The house is on a hill so it has only about 2/3 of a walk in unfinished basement and the rest is a small crawl space. Although there are a couple 2by4s blocking the hole to get into the crawl space I can remove those without making the structure any weaker. The hole to get in there is only about 20 by 40 so it is a tight squeeze. I may be able to saw at some of the cement to make that opening a bit wider. Once you're in there I am guessing there is about 2 feet to work with. Right now there is no insulation on the bottom of the floors above it and there is nothing but dirt and debris on the ground in there. I know this not acceptable so I am thinking I need to remove the debris, spray for mold, paint with mold resultant paint on the joint beams to be safe, lay insulation plastic over the dirt. I know there must be things that I am missing. I would be wearing a protective body suit while doing this. Do you think this is a project I should tackle myself or should I pay much more and get some quotes from contractors. Which type of contractors would want a job like this? Any advice is appreciated!