Network Services Forms/methods for tracking

Could anyone that operates in a ISP or large enterprise that deals with
many different customers/clients discuss some methods you handle network
service requests.

   - Do you have/use an online form?
   - How is it tracked, IE a service request #, circuit ID, etc?
   - Can the customer look up the info to see if their request is completed?
   - Can engineers reference this info when issues arrise, and customers
   call in for support?
   - Pros/cons about the method you are using now?

once the information is gathered how is it verified? (sometimes
clients/customers don't know what they need....)

and finally what information does the engineer receive to complete the
build of the network service?
does the engineer update the information when the network service is build
out so its tracked?

I am looking to get some feedback on some better ways to handle network
requests, service providers would probably have good feedback on this that
can facilitate collecting all the info needed, adding to the info once the
build is completed and then having something that can be accessed when any
t-shooting is required, and also if the service is to be decommissioned.

Any feedback is appreciated;