It would be helpful to know what values are actually contained in each of your variables.
Overflow occurs when you attempt to put a value into a variable that is too large for the variable.
It is unclear from your code how this could be happening.
However - you could get the Divide by Zero error easily enough.
The Clng would easily get the Overflow error in your scenario, but not the round - round accepts a huge floating point number that you are unlikely to be coming even close to with a loan calculator.
Woody Z http://www.learntoprogramnow.com