Equity is what belongs to the owner, not the bank, based on current value.
The value is based on the appraisal that the bank does as you are going through the financing process. Your loan divided by the value (Loan to Value or LTV) needs to be 70% or lower.
So, your equity will be the balance of (Value - LTV) or 30% or more.
Also, just because you provide the copies of the lease, it does not mean that it solves
the issue of qualifying. What if the rental income is not sufficient?
That's why it's good to have a financing contingency in your contract - to protect you, if you
are not able to get your financing (you tried your hardest but the appraisal came too low or
the rental income was not enough to qualify).
Best of luck and hope this helps,
Beachfront Realty, Inc.