Question
As a provider I want to eliminate the risks of the customers debts (used unpaid services) which concerns PACI subscriptions first of all.
Answer
It is possible to use Prepaid PACI model:
http://download.pa.parallels.com/pba/5.5/doc/61306.htm
More information about Deposit feature:
http://download.pa.parallels.com/pba/5.5/doc/61048.htm
Prepaid PACI model may be enabled by activating the 'FEA_CalculateNip' feature in the PBA database. More information about 'FEA_CalculateNip' feature may be found at:
https://kb.cloudblue.com/en/121412