Hi,
I'm new to Excel programming and would like some tip on how to calculate a
simple charge using vba.

Scenario:
For 100 unit and below, use $0.10 per unit
For 101 to 200 unit, use $0.15 per unit
For 201 and above, use $0.20 per unit

If I set cell A1 "Unit" to 150, then first 100=$10, plus next 50unit=$7.50

So cell B1 to show $7.50 as "Charges".

How do I code using vba?

Or is there a easier way, e.g using formula in worksheet without using vba
at all?

Thank you.