Send deposit refund or bill to all room mate tenants or one?

[Jack B.]

In the past I've collected the money from one person and sent the check out to one person. In this case I will need to deduct from their security deposit. They may get a partial refund or they may get a bill. I'm not looking forward to sending a bill via certified mail to ALL four of these tenants (they are all on the lease and all signed) but I'm guessing that I MUST?

In the past I did deduct from other tenants that were room mates and they agreed that one person would collect and disburse the money. With these people I'm a bit leery and I think I must send a bill to ALL of them especially if there is no refund and just a bill.