99 years lease details

In response to your query,

As per Section 17 in the Registration Act 1908, it is quintessential to register for leases and rent of immovable property from year-to-year or for any term beyond one year. This implies that if your rental agreement is of more than one year's tenure, you would have to register it.

The building records are kept at the local sub-registrar office of the city, therefore to learn about the building you are looking for you will have to put a formal request through a letter to the sub-registrar's office and tell them the valid reason for your interest in the documents of the particular building. 

Regards,

Aryan Raj