BMW X7 retails in the price range of Rs.98.9 Lakh - 1.04 Cr (ex-showroom, Delhi). Please click on the following link and select your desired city in order to check the estimated on-road price: On-Road Price of BMW X7
There is no difference between both the variants od BMW X7. The only difference is that xDrive 40i is a petrol variant and xDrive30d DPE Signature is a diesel variant rest all features remains the same.
For finance details, we would suggest you walk into the nearest dealership as they will be the better person to assist you. You can click on the following link to see the details of the nearest dealership and selecting your city accordingly - Dealers.