Reference: Fataawa ash-Shaykh al-‘Allaamah Muhammad Naasiruddeen al-Albaanee fil-Madeenah wal-Imaaraat – Page 246
Question: Is it permissible for a man to look at other than the face and hands of the woman he wishes to propose to, such as looking at her hair and her neck?
Response: That which is apparent to me – and Allaah has the Complete Knowledge [of all affairs] – is that that is permissible without any previous agreement [between the two of them to do so].
He ﷺ said – that which means:
«If anyone’s heart settles on proposing to a woman, then he can look at that which will lead him to marry her», [transmitted by Ahmad 3/334, and Abu Daawood 2082.]
As for [this occurring] on the basis of a previous agreement [between the two], then [in this case] it is not permissible to look at more than the face and hands [of the woman].