What you get back in trade in will depend on a lot of things..
One important issue is how you got into the first machine. for example,
Did you put down the bare minumam and finance the rest for as long as possible? in that case, you most likely are "backwards" or "behind the 8 ball" on that machine.
You mentioned that you have had the 20 for only a short time. Does that mean low hours, good mantanence, with no abuse? If so, that will work for you. Lots of folks want a modern, low hours machine.
Consider this sir; A new machine offers LOW intrest rates... as low as 0%, with 10% down. A used machine in this area of the country will require 20% down, and 7.75% for a maximum of 4 years. That makes a modern, low hours machine a hard sell if it is to be financed. On the other hand there a plenty of folks out there that will pay cash for it. And those folks get a modern, low ***, well mantained machine at a real good price. For example, I have on my lot a John Deere 445. 156 hours, clean as a pin, good looking, hydro, it has a little traler that goes with it, one tail light is busted out, runs like a top, sounds like a sewing machine.. Its a good, BIG riding lawn mower. its here on consighnment. The price is $7,000.00. you can get a new one with warrenty, low intrest financing for about 11 grand. It will take a cash buyer for this machine.
Steel is going up and up and up. Your machine will hold its value better simply because a new one just like it cost more.
Yes, you can do better by selling it yourself. After all, the dealer deserves to make a profit again because he will have to buy it back, set it on the lot, insure it, put his money at risk, sell it , Bla, bla, bla.
Don't forget to figure this in; you have some hours on this machine, you have recieved some benifit of the work this machine did for you. Your property looks better, perhaps there is now a driveway to the house, fence, cleared out some brush, or built the pad that a building now stands on... All this would have cost you someting if you hired it done. It cost you something when you did it with your machine also.... What is the differance between the 2 figures ?
Sometimes bigger is better. sometimes I need a bigger machine, sometimes I can do the same work with a smaller less expensive machine, it just takes a little longer. I work for me real cheap!
hope I helped virg