Formula question

Formula question

I have two dates, check in and check out, then a field that calculates the difference in days. So far so good.
Now i need to have a field (TOTAL PRICE) that takes that number of days and multiplies it by another numeric field (PRICE PER DAY) and add 55. Then I need another field (DEPOSIT) that calculates 50 times the number of days. Finally I need a field (BALANCE) that calculates the difference between TOTAL PRICE and DEPOSIT.

I would really appreciate some help here. I have tried everything and cant figure it out.

Thank you!!!