Если мне обращаться за консультацией, то было бы хорошо, чтобы текст письма подготовили бы Вы.

[valentinius]

Помогите, пожалуйста, перевести.

[kath]

Some options. All depends on how you want to sound.

If I must/need/have to seek a consultation, I would prefer it if you wrote the letter/it would be better if you prepared the letter/I would be grateful if you would prepare the letter/I would appreciate it if you wrote the letter. etc.