We are thinking of charging (in fact, we must use 'political' prices).
If I would charge, I would use the accounting records, (set accounting
on). If your server is mvs and you have sas/mics, this would be simple
if you prefer charging on a MB/day base. But I would expect one can
handle this with some c programming in unix. Or to put the accounting
records in some rdb.

Regards
Roger