You must be joking. € 550 for an OM mirror lens? No matter how rare the lens is, it is definitely not worth € 550. That is the same price as the 135-400, which is better, AF, auto aperture, faster AND real glass lens. The 100mm extra is something that is easily done in PS by upsampling, with better quality in the end than any mirror can provide.
no, I'm not, the price was about five-hundred-ish (could have too been € 520), I'm not absolutely sure, and it was sold rather quickly (I had my eyes on it and thought that if it were ever to go down to about € 450 I might try to haggle them down to about € 380 - no such luck) ---> on the other hand, I do not know if the lucky buyer did haggle them down ---> but then, on the other hand again, they have an auction house too (Westlicht photography or some such), they might have put it on auction and might have got even more for it, I just don't know
[another EDIT: this, of course, is with 20% VAT included]
this site is, by the way, with it's online prices more on the top end of the scale, but they are professionals, have a lot of old and very old stuff in their shop, and they do their repairs by themselves; also, everything I bought there until now [wasn't much, just some OM stuff] was in excellent condition (something you cannot say for everything you get on ebay)
ach, by the way, they still offer there my Canon FD 20/2.8 which I sold them almost a year ago:
https://www.leicashop.com/start.php?lang=de
I won't tell here how much they gave me - anyway, they paid cash and I can assure you that they won't make to high a profit on this one (though truth be told they had it more expensive on their site half a year ago ... which is quite fair and okay with me: they give me cash, they take the risk - although it's an excellent lens, Canon FD is difficult to sell these days -, and they have to live on something too)
first I thought probably I should have sold it elsewhere, but now I'm quite content and I'm really thankful for giving me cash and not selling the lens on commission (in which case I still wouldn't have got any money from this one yet)