Not sure what financing applications you develop. But what you suggest wouldn’t pass a code review in any financial-related project I saw.
Using integers for currency-related calculations and formatting the output is no dirty hack, it’s industry standard because floating-point arithmetic is, on contemporary hardware, never precise (can’t be, see https://en.wikipedia.org/wiki/IEEE_754 ) whereas integer arithmetic (or integers used to represent fixed-point arithmetic) always has the same level of precision across all the range it can represent. You typically don’t want to round the numbers you work with, you need to round the result ;-) .
Then I’m guilty of breaking the license. I have always been stealing code from Stack Overflow. Well, since I’m a senior dev right now I steal only from answers.