At the trucking company I worked at (semi retired now), every year was closed out. So data was archived. Check legalities where you live as to how long old transactions have to be available.
You setup a system that works for you as to the best way to carry forward receivables.
We just archived all paid and carried forward in a new year any not paid. Ditto for payables.
For accounting, see if there's a package that you can easily import certain data. We did our own custom accounting.
is a full on Double entry accounting
That should be seamless, handled in the background.
I have used Peachtree in the past (way way past). But see if Quickbooks has a trial, and play with it some and you will see how double entry is seamless.
There is also GNUcash. Only one I ever used is peachtree in the 1990's
Much of what you need can be done in a good accounting program.