We have a situation where we want to transfer a customer's actuals to a new sales rep, but we want to keep the budget numbers to remain with the current sales rep. How should we go about this in Anaplan?
This depends very much on your model and we cannot really answer it.
Broadly, I'd say you should copy the numbers onto the new sales rep, keep the old one and make sure the new sales rep is ignored when counting for the budget numbers. That is if you want to keep the detail.
Otherwise you can make a copy of the budget numbers in total, keep them in a archive module and just transfer those numbers + delete the old sales rep.