I shopped around for two years before pulling the trigger. I decided to stick with CAT because of the quality and resale value. I did have a little bit of experience with heavy equipment working in the coal mining industry for 6 years in the mid 70's. Other brands are cheaper but I have never regretted paying more for CAT. Their machines are heavy duty and overbuilt. Mine is a 74 model and it was being used daily on small jobs. I did a LOT of reading and lurking in heavy equipment forums. I looked a lot of different machines on dealer lots, online, and used Craigslist to find local machines I could check out. I am not a mechanic so once I found one I thought met all my criteria I paid a heavy equipment mechanic to go with me to check it out. He gave it his blessing and I bought it. All these older used machines have issues so you will have to deal with things but just make as sure as you can that there is nothing wrong with the engine and transmission and that is has a good undercarriage. There are some good online sites to help with evaluating a dozer so you know what to look for. You have to be diligent in your research and evaluation but in the end it is still a roll of the dice when you plunk down the cash. So far it looks like I got a good one. There is a demand for good older dozers that can work so I am not concerned about selling it. Shoot, with 55 acres of reclaimed mine land I may keep it till I'm too old to run it anymore. Sure are enough projects to keep me busy. Told my wife that at least I know how I am going to die - I'll work myself to death on this property :-)