I am trying to automate a price list, and get the sheet to return a selling
price on the variable cost price and markup amount. I have the formula:

=IF(D920,ROUNDUP(((D9+$P$10)+((D9+$P$10)*$P$3)),1 ),IF(D9<20,ROUNDUP(((D9+$P$9)+((D9+$P$9)*$P$3)),1) ,IF(D9<15,ROUNDUP(((D9+$P$8)+((D9+$P$8)*$P$3)),1), IF(D9<10,ROUNDUP(((D9+$P$7)+((D9+$P$7)*P7)),1),IF( D9<5,ROUNDUP(((D9+$P$6)+((D9+$P$6)*$P$3)),1))))))

D9 = cost price
p10 = uplift
p3 = sales tax to be added

This seems to work perfectly for the first two options, but returns the
second option for the other three. I have tried all variations of commas and
brackets to no avail.

Help would be greatly appreciated.

Thanks