Need help, situation has changed....

My husband is British, I am American.  We have one son who is a dual citizen.  My husbands parents are both critically ill, his dad is expected to die in next few months.  So instead of moving next yr, we are now looking to move asap.

My husband will be going over first, to obtain a job and rent a place for us to live.  My question is how much money for a family of 3 (Me, my husband and our son who is a dual citizen) does he need to make to be able to sponsor us?
Also have a 15 yr old daughter who may or may not decide she wants to move with us.  If she does decide to go with us, how much would he need to make then?

I am just so confused about all this.  None of the websites I have been looking at say exactly how much we have to have left over after expenses, and what expenses they look at when figuring this up.

Any help would be appreciated.  I would hate it if he took a job, and we filed and it was denied because he missed the mark by a few pounds.

I don't think there are hard and fast rules. With luck, someone will be along shortly to offer better, more specific advice. I just wanted to chime in and remind you that it's late here, so don't panic if you don't get many immediate responses.

Good luck to all of you!

Have a look at this thread for some info on money needed for the maintenance.

I know that for a family of 3, after you pay rent and council tax you should have 157.06 left per week.  It's based on some sort of benefits amounts - like what the government give a family that size to live on after paying their rent and ctax.  I think another child adds another 55 pounds or so.