1 – Salaat al-istikhaarah is prescribed if a person is thinking of some matter, as it says in the hadeeth: “If any one of you is concerned about a decision he has to make, then let him pray two rak’ahs of non-obligatory prayer, then say: Allaahumma inni astakheeruka bi ‘ilmika wa astaqdiruka bi qudratika wa as’aluka min fadlika’l-‘azeem (O Allaah, I seek Your guidance [in making a choice] by virtue of Your knowledge, and I seek ability by virtue of Your power, and I ask You of Your great bounty)…” Narrated by al-Bukhaari (1166).
If a woman receives a proposal of marriage, it is mustahabb for her to pray istikhaarah and ask Allaah for guidance as to whether to accept this proposal.
2 – With regard to salaat al-haajah, which is mentioned in the hadeeth of Ibn Mas’ood (may Allaah be pleased with him) from the Prophet (peace and blessings of Allaah be upon him), who said: “Twelve rak’ahs that you pray by night or day and recite the tashahhud between each two rak’ahs. When you recite tashahhud at the end of the prayer, then praise Allaah and send blessings and peace upon the Prophet, and recite the Opening of the Book seven times whilst you are prostrating, and say: Laa ilaaha ill-Allaah wahdahu laa shareeka lah, lahu’l-mulk wa lahu’l-hamd was huwa ‘ala kulli shay’in qadeer (There is no god but Allaah alone with no partner or associate, His is the Dominion, to Him be praise, and He has power over all things) ten times. Then say: “O Allaah, I ask You by the glory of Your Throne and the Mercy of Your Book and Your greatest name and Your highest majesty and Your perfect words,” Then ask for what you need, then raise your head and say salaam right and left. Do not teach it to the foolish for they will pray and will be answered.”
This hadeeth is not saheeh, rather it is a false, fabricated (mawdoo’) hadeeth, as al-Albaani (may Allaah have mercy on him) said in Da’eef al-Targheeb wa’l-Tarheeb, no. 418.
3 – There is no specific du’aa’ concerning marriage that is called du’aa’ tayseer al-zawaaj (du’aa’ praying for marriage). Rather a person may ask his Lord to bless him by His bounty and to facilitate good for him wherever it may be.
4 – Working as a musician or drummer is haraam and the payment received for that is haraam wealth, because of the reports in sharee’ah which say that musical instruments are haraam. See the answer to question no. 5000.
Based on this, you should advise this man. If he repents to Allaah and gives up this work, and finds a permissible job, there is no reason why you should not marry him. If he continues with this work, then there is nothing good for you in him, because his wealth is haraam and he is persisting in doing something haraam.
We ask Allaah to bless you with a righteous husband and righteous offspring.
And Allaah knows best.