Help I want the result of a formula to have a minimum value

I'm preparing a spreadsheet with some formulas where it calculates a cost to charge a customer.

The formula in 'Calculated Cost' currently read as follows; =SUM(A2*50)+30   This works perfectly as required. (£30 is an admin fee).

What I want to be able to do is to either modify this formula so that if the 'Units of' was for example 3, the result would be £180 but I want the amount to be charged to be £200 (as a minimum charge.

Ideally, in this scenario, £200 would automatically appear although as you'll see, I'd be happy to have the 'Amount to be Charged (Min £200)' in another cell.

Anybody know the exact formula to get this desired result?

Thank you in advance,

Paul