Because nobody has or probably will run the exact configuration like you, you could do a test install on a local box with the same size of disk or FreeBSD slice. Use the advice of jggimi, by putting everything in a single giant "a" partition/label and calculate the sizes from that.
You can calculate those sizes with "du"
Code:
j65nko@hercules[~] du -hs /home/j65nko
5.1G /home/j65nko
j65nko@hercules[~] du -hs /var/log
1.1M /var/log
See
du(1).
I thought I already posted this several days ago, but apparently I forgot to click the "Submit Reply" button