Datacolor User to User Support Group.

i hope my question here is not too elementary...  anyway...

i just got my PFPro Suite and i'm starting to use it.  so far, it's
working fine.  i still have to do some more tests.

PFPro Suite users use this for various printers - inkjets, lab
printers, large format printers, etc.  the frequency of printing
varies for a lot of us.  some of use may print heavily on our inkjets
while some goes to the lab for majority of their prints and seldom use
inkjets at home.

my question is, how often should we build a printer profile?  

if we use inkjets, should we build a printer profile,
a. everytime we replace inks
b. after every x number of prints
c. after every x number of days

if we go to the lab for prints, should we build a printer profile,
a. everyday
b. after every x number of x size prints
c. after every x number of days

my follow up question is, how often should we calibrate our monitors?

do we calibrate our monitors,
a. everyday
b. after every x number of days irregardless of monitor operation
c. after every x number of hours of monitor operation

regards,
david