Omega Dynamic

Today I went out with a local Sri Lankan colleague who loves watches, he took me to the local antique watch dealer to check out some fine watches, like Rolex, Tudor, Omega, etc...
We came across a shop that he recommended, small shops but he got a handful of antique watches on hand. The only watch that catch my interest is the thirty years old Omega Diville Auto with leather strap that he showed me (Off course the leather strap is not genuine because no such leather can last so long). Before I asked him the diville selling price, he notice the Omega Dynamic Chronograph Automatic (year 2000 model, final edition of Dynamic)that I was wearing. He asked me how much I bought my watch, I told him USD600. He said right now the price of my watch has shooted up to about USD1500! I was surprised to hear that, perhaps is the Euro currency rate increased.
Well, I bought this Omega watch like 4-5 years ago, at that time, the market rate is about USD 720+ and one day, while I was surfing the internet, I found out the watch price fell to USD580+ probably is due to the bad sales in US. Without hesitation, I log onto the website and purchase it online. The Omega Dynamic is quite thick, may be around 1.25cm, and comes in without date indicator, this is the reason that I seldom wear it to work because it doesn't tells me the date. The movement of this watch is very reliable and accurate for an automatic watch (especially compare to my Oris and previously owned Tissot). I gave it to my dad as a present when I first went home from US, my dad only wears it once in a while thus the watch was left into very good condition before I took it back and wear it once in a while.
Just few months ago I check the used price at ebay and I still found out that this watch was selling at 7xx.xx USD before the bid ends. Well today this watch dealer saw my watch and shows great interest on asking me to give him an offer to sell it to him. My colleague felt that it is quite funny because we suppose to come here and buy watches but could end up selling watches. I told the dealer in a joking way that if he pays me USD1200 I will sell it to him. He said he can't.
Then I ask him how much he wants to sell the Deville, after some bargain, the price of the Deville came down to USD110 which I think is a good buy. I didn't buy the watch yet but I am very interested on that watch. Before we go, the dealer offered me USD800 for my watch and I told him I will think about it, I took his name card because I don't think I know how to come back to his shop because it was located at a very crowded place, hopefully we might strike a deal later. For USD800 I don't think I want to sell it because USD value has depreciate since few years ago, and with the money I got, I still have to top up another 40-50% for a Seamaster. Will see what happen...