What security do I have to furnish?
Since this is a housing loan thus bank requires a mortgage of the property for which the loan is being taken.
Is it possible to apply jointly with spouse or other blood relative?
Surly joint application can be processed but decision varies bank to bank.
What are the time line to process a loan application ?
In Retail loans 7 working days once documentations are completed
What is the validity of this letter ?
Validity of an In-principle / Pre-Approval letter varies from 30 days to 90 days, depending upon bank to bank.
Can I get an in-principle / Pre-Approval Letter and actually avail of the loan later ?
Surly, In-principle / Pre-Approval letter can be issued to you based on your income. After receiving letter you can plan your budget for property.