I guess it all comes down to "my fair market value" and" their fair market value" as promised four years ago when I bought the SG. We should of clarified then.
I have learned my lesson, and I apologise for saying rip-off. I should have used a different phrase, but I can't edit it now.
IMO, you did get ripped off. There is only one definition of "fair market value". Not yours or theirs.
From:
http://www.investopedia.com/terms/f/fairmarketvalue.asp
What Does Fair Market Value Mean?
The price that a given property or asset would fetch in the marketplace, subject to the following conditions:
1. Prospective buyers and sellers are reasonably knowledgeable about the asset; they are behaving in their own best interests and are free of undue pressure to trade.
2. A reasonable time period is given for the transaction to be completed.
Given these conditions, an asset's fair market value should represent an accurate valuation or assessment of its worth.
What they offered you was wholesale value. What they promised you was resale value.
f64: The following link lets you know every SG that’s for sale across the US that’s not in a store.
Link Removed
Right now there are 1279 SG's for sale on eBay, CL and other platforms. The average sale price asked (asked on CL isn't what it goes for and the eBay prices move) is from $ 600 to $700.
Based on on the above, you should have been offered $600-$700. or even the $550 to $650 that was posted. Depending on condition.
Next time, get everything in writing and if they promised "fair market value", include that as well along with the definition.
Obviously, the promise was made to you to get your future business and w/o consideration of how much money they would make on your trade-in. Or consideration of how much time has passed.
I suggest you speak to the manager/owner and explain your situation and let them know the name of the sales person that made the promise to you. Bring him/him some info as far as what SG's are going for on the open market. Ask for the $600 you think is "fair".
Best thing to do is keep cool when discussing the situation. If you have receipts from past purchases, I suggest you bring those along with you to prove that you're a very good customer.
While they may have many customers, repeat customers keep them in business.
Since you were in the process of purchasing more equipment by applying the trade-in amount to your purchase, maybe you can ask for additional discount on the item you were going to purchase? Maybe there's leeway in their new equipment profit margin as opposed to their trade-in value?
Whether you shop there in the future, well, just let them know it's up to them and how they treat you now by resolving this situation in your favor.
Hopefully you can get them to work with you. If you still cannot get them to give you what you were promised, consider it a $250 educational lesson that you paid for the hard way.
Good luck.