Dear Mr.... We are really interested in the equipment manufactured by you. Please, send us a detailed offer so that we will be able to plan our investment. Our research showed that working with your equipment would be beneficial for us.
Poznámky k překladu
manufactured by you = manufactured by your company
"The equipment manufactured by you represents a serious interest for us."
That would be natural in English as:
"We are really interested in the equipment manufactured by you (your company)."
and "Please send us a detailed offer so that we'll be able to plan our investment."