Dear :

Thank you for ordering from [company]. The merchandise will be ready for delivery in [days, weeks], as you required.

There is, however, one point we need to discuss with you. We would like the last % of your order to be paid within days of completion, rather than the days your have suggested. Please inform me as soon as possible if this is agreeable to you.

Thanks again for choosing [company].

Sincerely yours,

[name]

[title]