Smallest unit also has issues. For instance the Indonesian rupiah technically is made up of 100 sen, but the currency is so inflated nobody uses it and currency libraries behave differently (even different versions of the same library). We had a bug where different OS versions provided different values when normalizing it to a smallest unit integer.

If you really don’t have access to a decimal type I think the best solution is to convert it to micro-units (price * 10^6). This is what Android does in its billing library.