Regarding Estimated cost spinner, the problem is that type="number" is not fully supported on IE https://caniuse.com/#search=number .
The field is still verifying if the input is numeric. But there is no warning regarding this, just that the value is not saved and you have to retry. The spinner would have clarify the fact that there should be a number and besides this I don't think is very usefull.
My question is if we should find a workaroud for having the spinner on IE or it would also be usefull to have some warnings or a hint on the input instead?