In Finland on an online secondhand shop these N9 phones are asked 20Eur to about 70Eur. If the condition is not prestine collector item I wonder why anyone should or would pay over a hundred for a phone with no support and with (as it seems) a lots of problems. N900 are asked about 60-70Eur but there have been the same on sale for the last year with that price, with boxes and stuff and on a working good condition. If you really like the phone I suggest you just continue playing with it and try to get money selling something else. I doubt you get the price you would like to get.

Edit: They sell N9 phones with 20-70Eur. Some ask more but it doesn't mean they get them sold. For some time there were N900 phones with a price tag 100-150Eur. Now they have dropped them to 70Eur but it is still too high price and they aren't sold. I have bought N900 phones with 20-30Eur and I always sent that offer to new sellers. Best buy was 3 working and 1 with only wifi N900 phones with 35Eur.