me three
Normally, for new customer, you ask the phone number and address.
Then if s/he order again, you will know the address by the phone number.
Even if you already have the address in the database, I would strongly suggest to confirm again the address because there is still a small chance that the customer moved.
Now, let's say you can integrate the post office database into samba pos!
I would say, most of the time the phone number would be the land line and not cellular phone number that's why the number would be 90% correct (10% would be if the customer change a new number if they moved, for this case those who live in apartment)
Thus, most probably you won't have their cellular number. And how many people using cellular phone now?
Even let's say, the post office get their cellular number. How accurate is their location when they make the order?
They can order for the office, or their friend (if they were watching let's say soccer together at friend's house), or if they stay in hotel?
Thus, their address can change!
So, assuming their address never change would be a mistake!
It would be wise to double check their address again!
Just my two cents!
Regards,
Leon.