1. Dowry is a pre-requisite for a marriage
2. It is to be paid by husband to his wife
3. It should be equitable
4. The husband and wife can mutually make any adjustment to the dowry
5. Forfeiting of the dowry does not apply to believers.
Although I do not find in the Quran any support for payment of dowry in cash only, I do not think that dowry could be something which does not have a monetary value thereto. It cannot be love, honesty, being faithful, etc. which are anyway traits of righteous people. This conclusion can be drawn from the verses which deal with giving back / forfeiting dowry in certain circumstances. Dowry could thus be paid in kind as well but it should be something which has a monetary value.
What is an equitable dowry is what one has to assess for himself. It depends on case to case. The rich as he can and the poor as he can. This should not be abused for God holds us responsible for our innermost intention. When we are committing our deeds with an intention to please Him, He will guide us to do the right thing.
Although one may get a feeling that there is an escape to dowry in view of verse 4:4 – You shall give the women their due dowries, equitably. If they willingly forfeit anything, then you may accept it; it is rightfully yours., it is actually not so.
It is not correct to take back the dowry unless one is completely overcome by certain circumstances.
**Late Dowry: Should be paid when a woman is divorced, or the man plans to go to Hajj, or when he dies.