Rental property in india

My wife just inherited a property in India and we are going to rent it. The rent is expected to be 10 Lacs a year.

- Is 30% deduction straight allowed on the property with no questions asked - does it mean only 7 Lacs is taxable? What IT rule governs that?

- Can depreciation be claimed on the cost basis of the building if only income is rental income for the owner ? If Yes, how much can be claimed ?

- Can any other expenses we claimed also to save taxes?

Regards