I have had a couple of root canals and caps. Two things I would recommend:

1. Don't get the tooth pulled just because it is cheaper. If you have other teeth problems later you might need this tooth as an anchor for bridge work.

2. Since you are paying cash you can bargain with the dentist. He/she might let you pay on a time plan. Medical people will cut you some good deals just so they do not have to mess with insurance. Try bartering. My next door neighbor did a lot of house repairs for the dentist that owned the place in order to get teeth implants. It never hurts to ask.