Updating ABO asstets and configuration from customer portal

Currently we have an ABO setup where most line items are children of a "Service Location"

Here is an example of what we are trying to do.

We make a signup quote to create and account with a line item asset that has quantity 10 a a specific location.

On our customer portal the customer moves 2 of their licenses to a different location.

Some API calls or something??

We make a MACD quote on the account and we see the first location has quantity 8 and there is a new asset at the second location with quantity 2.

Do you have any guidance on how we can achieve this without creating a new quote every time. What is the best way to make a new asset? What is the best way to update config data? Is there anything else that would need to be updated for this to work cleanly?