Dear
This letter will confirm [individual's] telephone conversation with you today concerning an increase in our billing rate to [amount] per hour， effective [date] It is necessary that we request this increase due to a rise in the cost of conducting our business. We are faced with an increase in payroll taxes and insurance， along with an increase in our overhead costs. In addition to the above，we also seek a modest profit.
Attached are copies of our service agreement and we request that you sign one copy and return it to us indicating your approval of this new rate.
Dear
After careful review of your charge account， it pleases us to inform you that we have increased your credit limit as follows：
OLD CREDIT LIMIT： $
NEW CREDIT LIMIT： $
Furthermore， this change in account status qualifies you for use of our installment account. Should you require additional information about this new account， please see one of our credit representatives the next time you are here for a visit.
You are a valued customer， and as such， you will be advised of our special customer sales， which we have from time to time. We appreciate your continued patronage， and look forward to being able to assist you in the near future.
