Re: Mehr
Mehr is up to the couple to decide. Like in Prophet PBUH days , mehr had been declared a silver ring or some piece of clothing.Times have changed so whatever groom can easily pay to the bride. Marriage isnt about the mehr but mehr is a form of security given to the wives in case anything goes wrong (or even if it doesnt, its a gift to her from the groom.)
Mehr can be paid at the time of nikah or the other way is that groom pays a part of it at nikah time and rest at later times.
And if u are asking how much should u declare then salary of a month or 2?