Maybe you feel ebay will make the price too high, so sell it however you wish, but don't be a chump. 200 Euro for an A4K, even if it is bare?
The A4K was at one point every serious amiga users fantasy. I'd take it for 200 but then I would be taking you for a ride. Don't listen to anybody telling you that it's unrealistic to expect to get a much better price (as long as its in good condition), they all want to grab this machine on the cheap.
It is a sellers market. Good luck dude :-)