Can you please polish this sentences to make it more polite and businesslike?

Question

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It is with regret that I have to inform you that the fee for my localization services have increased from USD 300/project to USD 450/project.

I have informed your staff about the new tariff when she asked for quotation and she has agreed with it. However, I will still charge the previous services that I have delivered to you at old price. Thanks a lot for your understanding.

Answer 1

It is with regret that I have to inform, the fee for my localization services have increased from USD 300 per project to USD 450 per project. I have informed the (mention the department of the staff) about the same, when (specify who is "she", give a name Ms.....) asked for quotation and it has been agreed upon. However, the previous services will be still charged at old rates. Thanks a lot for your understanding.

Answer 2

It is with regret that I inform you that the fee for my localization services has increased from USD 300/project to USD 450/project.
I have informed your staff about the new rate when asked for a quote. Your agent has agreed with this amount. However, I will continue to charge the older price for all the services that I have performed before. Thank you for your understanding.

Answer 3

how about this???

regretfully the feeS for my localization services have increased from USD 300/project to USD 450/project.

i informed your staff about this new tariff when she required a quotation, and she accepted my new price. however, since you weren't informed, i will charge this past service according to my old price. in future, the price will be USD 450/project. thank you for your understanding.

Answer 4

I am sorry to have to raise the fee for my localization services from $300 USD per project to $450 USD per project.

You staff asked for the quotation and was informed at that time of the new tariff with which they agreed. I am happy to be able to provide previously contracted services at the old price.

Thank you for your business and your understanding in this matter.

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note: "staff" is generally used in the plural - so there is no agreement when "staff" is used with "she" which is singular. If you want to use "she" you could use "assistant" or "colleague" instead of "staff".

Answer 5

Here it goes....
"I regret to inform you that my localization service fees have increased from $300 to $450 per project.
The new tariff has been informed to and agreed by your staff personnel, when she asked for the quotation. However, the the previous services delivered to you will be charged at the old price.
Thank you for your co-operation"


ALL THE BEST !!!

Answer 6

Regretfully, I must inform you that I have increased the fees for my localization services from three hundred dollars($300) per project to four hundred dollars($400) per project.

I have already notified your staff member about the new fees at the time she asked for a quotation. I will however charge the old price for any services rendered prior to the current increase .

Thank you for your cooperation and understanding.

Answer 7

My 2 cents....

As a reminder, it has become necessary for the fees for localization service to increase. The current rate is USD $450/project, as previously quoted to your staff.

Completed projects already delivered will be billed at the prior rate of USD $300/project.

Please make note of the changes for future reference, we appreciate your understanding, and look forward to providing continued services.

Answer 8

For the second paragraph:
I have discussed this change with (name of staff) and we are in agreement. Previous services rendered will be billed at the original price. Many thanks for your understanding. (It is a pleasure doing business with you.)

Answer 9

I would use per instead of /
Leave out "have" between I and informed.
A comma after quotation.
at "the old price"
Leave out "a lot".