Claim Approvals

I am new to Bizagi, and require some guidance on a process that I would like to create. I have a need were the request is made to approve a claim. During the request, the requester lists the people that are required to approve the claim. These could be different combinations of people, and may change from claim to claim. Also ability to forward an approval or change approver if need be once the processes has started. Also number of approvers can change from 3 to 5 or more depending on the requester's selection(not a set business policy). Once all the approvers approve the request, there as email that gets sent out to the list of confirmations users. What is the best way to go about this?