Generally, what council you are in depends on where your meeting place is, and where the members of your Troop live.
If the leaders, and girls, all live in your city, and the Troop meets in your city, you are pretty much stuck with the council you are in.
I would recommend talking to the other council first to see if, come October, the girls and adults could all register there.
If allowed to join the other council, you would have to have a brand new Troop set up, in that council, with a new Troop number.
As to bringing Troop funds with you to another council, I would guess no, that would not be possible. Your Troop is "owned" by your council. Your council's name is on all paperwork, including the checking accounts. This is why you are required to file a financial statement with your council every year.
Why do you want to change councils?