[Alex4386]

If you connect two or more telecom lines into your rack or any service, you need to pay "Cross-Connect" fees. This is paid separately even if you brought your network line by your own. I can't say how much price is it since it is mostly trade secret with the sales dept of the telecom. but I'd say its a lot.

[rsingel]

Usual fees for cross-connect are low and one-time. It's charging for data into a network that cause the issue.

[elliewithcolor]

Transit yes; Deutsche Telekom AG is one of the worst in Europe. While telia charges something in the range of 10-20ct per Mbit; DTAG charges 80ct.