This is especially important if you are struggling to make regular monthly payments. While many lenders will allow you to extend your mortgage, they may want to carry out an affordability assessment, although usually, if repayments are being lowered, this won't be the case. They will also weigh up your age.
In some cases, you may be able to negotiate with your finance provider to spread the balloon payment over monthly instalments – this is essentially what refinancing is. Doing this can help make the payment more manageable and reduce the financial strain of a large lump sum payment.
If there is a "balloon payment" (final balance), enter it into B4 as a positive value, and use the formula =PMT(B2, B3, -B1, B4). Those formulas also assume that payments are at the end of the period (i.e. end of month). That is typical. However, for car leases and such, the payment is at the beginning of the period.