SO I'm trying to create a spreadsheet that calculates costs for rental equipment. They charge a daily and a weekly rate, so if I rent an item for 1 week and 2 days, I get charged the weekly rate, plus two days at the daily rate- no prorating. I was able to make a formula to calculate this part- I'm using:

=INT(DATEDIF(G2,I2,"d")/7)&" Week(s) "&MOD(DATEDIF(G2,I2,"d"),7)&" Day(s)"

to calculate the difference between ate of pick up and date of return. However, after 5 days, they round you up to the weekly rate and I haven't been able to make a formula work with this. Any thoughts?