Welcome to FT!

Yes, costs are in addition to 600 EUR compensation. The hotel/accommodation costs are to be reimbursed by TK (if 1 ticket and TK made you miss the onward flight due to TK flight arriving late). However, to get reimbursed for replacement ticket (I assume for subsequent segment that you missed due to the delayed TK flight) I doubt TK will reimburse that. You should have talked to TK or the airline performing the leg that you missed about rebooking to the next flight; if on 1 ticket it should be no issue to rebook. TK could have done that and also the airline that was operating the flight that you missed. Did you try to talk to someone about getting rebooked rather than buying a new ticket?