Rule reminder
Formal requests in Italian use: conditional tense ('potrebbe indicarmi', 'sarei grato se potesse'), indirect structures ('avrei bisogno di sapere', 'desidererei richiedere'), and hedging ('nel caso in cui fosse possibile', 'qualora lo ritenesse opportuno'). Direct imperatives and the informal 'tu' must always be avoided.
You need to ask a client for their contact details. Which phrasing is most formal?