Not everyone is on a 5:3. As you were interested in LCY and AMS base, the UK crew are on a 6:3, the AMS hasn't opened yet.
SO basic salary is around £23k, with allowances on top of that. None of the RHS are doing much flying at the moment, though in time that will change. Budget between £500-£1500 (net) in allowances per month. The AMS base will reduce overnights but noone knows by how much. Be careful paying for an RJ TR - you'll find yourself bonded onto the SSJ anyway.
Flyingfisher is accurate.