In terms of the type of (income) gains, that would be dependent upon the nature of the assets.
However, I will page @Rick19744 and, hopefully, he will respond shortly with a comprehensive answer.
In the interim, below are a couple of threads that may be of interest to you.
https://ttlc.intuit.com/community/business-taxes/discussion/installment-sale-of-membership-interest-...
https://ttlc.intuit.com/community/business-taxes/discussion/re-sale-of-llc-interest/01/2033099#M6749...
