Freighters would have 10 people max, since they're small and probably don't have much living space.
Gunboats' sizes are just bigger than freighters, but I'd say since they're military oriented they'll need a few extra people for boarding and security. 25 at the most, if the gunboat's primary duties are to transport boarding troops. 10 for a bridge crew and the rest for utilities and maintenance.
I'd imagine transports would be automated and computerised. Also, they'd have to cut living space to carry as much cargo as possible. So just around 20 for them.