To me "business" implies a real need. If there is no real need, it is personal.

Solozzo + McCluskey = business
Five families = business
carlo = personal
Tessio = business
Fanucci = business
ciccio = personal
Roth = business
Fredo = personal
Pentangeli = personal

I have left the GF3 murders, I haven't really analyzed them or particularly care.