Definately do it yourself! Even with limited skills it is very hard to mess up and you could probably save enough to buy a set of Rancho shocks. I charged my wifes van a few days ago, it already has the R-134a, and I only needed 2 cans which cost $4.50 each. About 6 or 7 years ago, before I was enlightened, I took my car in to be charged and it cost me $120.00. I suggest going to a Wal-Mart ect. and looking at the conversion kit and read the instructions for better understanding of what we are telling you.