Regardless of whether the first contact with a potential business partner was made over the phone, whether there was an oral agreement, in the practice of business turnover there is a custom to support the beginning of a relationship with an official letter with an offer of cooperation.
In the first part of the letter, which is no more than one paragraph, write what kind of company you represent and greet the management of the prospective partner on its behalf. It is appropriate to use phrases such as “Our company wishes your business prosperity”, “on behalf of such and such company we express our respect to you”. Be sure to include the name of your organization. Remember that in the form of spam, more than a dozen letters come to any company with a proposal to conclude an agreement, so the addressee should immediately understand whose proposal is being discussed.
In the next part of the letter, remind the potential partner that there were already preliminary agreements between your companies on a specific contract or service. You can use such phrases as "In continuation of our negotiations …", "We have considered your wishes regarding …". Make it clear to the addressee that this cooperation offer is not a template and basic, as for all clients, but is developed specifically for this company, and takes into account all the features of this particular business.
In the largest part of the offer, indicate which services or goods you offer, what is their cost, delivery time. The information presented in the tables is easier to understand. Offer the client several options with different cost, quantity and volume of services provided, so that he can choose the most suitable combination. Highlight the benefits that the client will receive by concluding an agreement with your organization. Here you can indicate discounts, special offers for regular partners, the possibility of concluding contracts for the provision of additional services or the supply of other goods on extra-favorable terms.
Dedicate the last part to wishes and parting words. Use standard phrases, for example, "We hope for mutually beneficial cooperation …", "Best wishes …". Be sure to subscribe and leave your coordinates, so that in case of a positive decision, the client does not look for a phone number or e-mail address where you can be contacted.