for instance:
this motobecane has a price of 749(!)€:
a columbus sl frame with some random dura ace parts and tubular tires (for the city??)
and this belgian diamant for 849(!!!)€:
some (obviously used) campy parts and a reynolds 531 frame. nice chainguard though.
they look quite nice but come on guys! give me some time and i build you equal bikes for the half of the price! don´t forget these are only converted old steel frames!!! have you ever hurt your knees on left over braze-ons on such a conversion frame? its hell i can tell you. there is absolutely no justification for these prices and the profit margin has to be at least 100%. for around 800€ people wanting to buy a complete-bike can get new one such as a bianchi pista via condotti. or even building up a nice trackframe with brake drillings as a singlespeed is cheaper than that! the guys didnt even know that this isnt a german diamant before i told them via mail.
so. it´s nice to see old frames refurbished and off course old and good 10 speeds might be harder to find than 5 years ago but if you start a business like this, take a appropriate prices. and if you´re willing to buy a new bike: don´t believe the hype. don´t buy expensive conversions.