I have a spreadsheet that I am creating that I would like to auto calculate
except for a few cells. This is the jist of what is happening. We pay 100%
the first $500 of an expense. After the first $500 we pay 80% of the next
$1250. I am tracking these expenses for each person. I would like to only
have to enter the expense amount and then nothing else. I have created most
of the spreadsheet but am having problems with the 80% part of it. I have a
formula that works for the very first time the 80% is used but am stumped
after that. This is the formuala I have that doesn't work past the first
time. =IF(G10+B11<=$C$5,(B11*G4),0)

G10 being the total of previous expenses
B11 being the new expense
C5 being the total expenses allowed for reimbursement ($1740)
G4 being 80%

I would like to add an "and" to the formula but am not sure if that is
possible.

Hopefully I made sense. Any help would be greatly appreciated.