Re: Buy used Force 120???
Force engines are not desireable and command a lower price that same year Asian or OMC/Merc engines. Prices range all over the place depending upon condition and of course, you can expect the shop to be higher end. Best I can offer is to look on the auctions or Craigslist for comparables.
As a private seller, I would expect to to try to sell one of my 125s for around 1500, however, I did take 1000 for a 120 and also a 90, each was in very good condition..
Mind you, this is with controls and prop. (I have a lot of Force and Chrysler engines)
Again, if it is a Force built by Mercury with Mercury ignition, it would be worth a little more than an early 90s engine built by US Marine.
In the end, what you end up paying really depends upon how badly you want to buy the engine and how badly they want to sell it.
Don't forget: A new prop will cost over 100 bucks, double that for stainless, and good condition used props are all over the place in price--but factor in at least 100 for a prop. Even though you can do well on the auctions, also factor in 100 for controls and cables (used) if the engine does not come with them.
Now, there may be those naysayers that will jump in and tell you that the Force is only good for an anchor. In real world, you may or may not have a problem, and the engines do not equal the performance of (for example) a 120 Merc.
HOWEVER: these engines are easy to work on and parts are still available even though the line was discontinued in 1999. Keep 50-1 TCW3 oil in it and do minor maintenance and the engine may just outlast your boat.
Also: Since the engine has no history with you, change the lower unit oil and water pump impeller in addition to the fuel pump diaphragm, or have the shop do it as part of the purchase agreement. Also have them run a compression check in front of you. All cylinders should be equal and over 120--145 is about optimal.