My question is regarding the conditions of mut’ah which I’m not able to understand.

1) I actually came in touch with a girl online few years back who lives in another country. Last year she reverted to Islam. We intend to marry each other but due to financial issues we are not able to do so at the moment.
She is the only Muslim in her family and rest of her family follows Christianity. So if we intend to make a temporary marriage do we need consent of her father? Also, do I need consent of my family? until we are in a position to get permanently married if Allah wills.

2) Also, can we do mut’ah ourselves or do we need any contract or a religious cleric?

3) Apart from that, is only money allowed in Mehr? if so, is there any minimum amount for it?

1- Since she is Muslim and her father is non-Muslim, she does not need his permission for marriage (whether temporary or permanent).

2- You do not need your family’s permission to conduct the marriage contract.

3- You can have the marriage contract done directly between you and her. You don’t need a scholar to perform it for you.

4- There is no minimum for the dowry. Anything that has value qualifies. So anything that has value in the eyes of society is ok as a dowry.