Accurate cost of any treatment can not be predicted here. Cost depend on various issues. Approx cost of RCT may be 2500/- and cap charges also may be 2500/-. You should consult to your local dentist for accurate charge inquiry.
Charges for scaling who is depend upon the amount of stains and deposits your teeth have and will also depend upon area and the clinic that you opt for usually somewhere between 800 to 2000 should be good enough and duration of getting it done is somewhere around 1 year if you brush properly.