Durst M370 BW
Durst was my first choice in terms of low budget enlargers. I have found it on ebay-kleinanzeigen for 80 euro in vergrößerer category.
I think it is a really good starter for someone who is not sure about investing more in photography. Berlin has a relatively big community of people interested in analog photography.
The M370 is a lower end condenser enlarger produced in Italy. What does it mean? Basically, if you want to print something from a larger film than a standard 35mm picture, you will need to invest extra to get the dedicated condenser. For example, if you like to play with a 6×6 format, your enlarger will require Durst Lidicon 100 condenser and 80mm lense.