im sorry dude, but i think you're a dick here. he offered something but you started the d-baggery. he is reasonable, and he's most certainly right about what he's saying. good luck selling a used M3 for over 49k. the first year you use the car, in fact, the moment you take it out of the dealership it takes the biggest hit on its value. it doesnt mean (like the 2nd or 3rd post says) that in 2 years it'll be worthless. check KBB, although in these times it's super fucking hard to sell a car at KBB.
also dont forget that people usually "pad" their asking price. so typically if you want to sell for 50k you would list it for 53k, and on the other hand the guy wants to pay say 48k so he offers 45k... so u guys, with civil negotiation, will reach a figure in the middle.
it'll eventually stabilize and depreciate less later.
you sir certainly lived up to the bad reputation of snobby rude M3 drivers