This a old thread . it was writed before the proforma option was added . and all now is added to blesta except what was mentioned in the other thread .
1 sequential numbers for proforma
2 storing client details in invoice . don't be changed .
"Client ID" are unique number so in what it's differ with "client account ID", as it's ever what it is or mean by now.
What's your need behind the word "account", may you develop more?