There are two charges in sale deed.
Stamp Duty - Stamp Duty is decided by sale value or market value of property whichever is higher. Stamp Duty is some per percentage of sale value or market value whichever is higher.
Eg. if sale value of a mumbai property is 1 cr and market value of that property as per ready reckoner rate id 1.1 cr then stamp duty will be calculated on the 1.1 cr as if has higher volume. Consult a legaldocs expert get your stamp duty calculated.
Registration Fees - Registration fees is also a variable of sale value upto certain limit then it is fix for all value above certain limit.
Eg. registration value if 1% of sale value or 30,000/- whichever if higher.