1) For rent more than 50,000, you need to deduct TDS one time either at the of leaving the property or in the month of March. You need to deposit it with the govt.through challan cum statement Form 26QC.
2) Rate of deduction would be 5%.It will be on total rent i.e. 55,000
3) Yes you need to deposit for a property where the rent exceeds 50,000.
4) Yes you need to pay rent after deducting tax.
5) You are not required to mention in your ITR.
6) Yes there is a penalty of equivalent amount.