Tracking Mileage from Ticket Transactions

Hi,

Firstly, I’m just getting back into RT after changing jobs, so It’s been
4 years since I started to work on customizing RT.
We run a IT services company, and we’re looking for a nice easy way to
track mileage on a ticket transaction.

What I’d envisioned is inside a ticket transaction, have a custom field
similar to Time Worked, where you can enter a value and have it
increment the total value in the way that time worked happens.

I assume I’ll need two custom fields, Mileage Total and Mileage, and on
Ticket Submit, take Mileage and add it to the Mileage Total value, is
this correct?
I would also like to keep a monthly log of mileage, so on ticket
submission, if there is a Mileage entry, create a comment in a different
queue called “Mileage Queue” where I’d have a ticket for each user, each
month.

The first part seems simple enough to do providing I’m in the right
path, and the second will take some playing around with I’m sure, but it
seems possible. Before I get too caught up, is there anyone that has a
similar setup that could post their configurations?

Thanks,

Chad