If I ever needed to assemble a “history” of the in-and-out of monies within tax-advantaged accounts, which are the best forms to do that with? For example:

– W-2 forms would list 401(k) contributions
– 1099-R forms would track distributions
– 5498 forms would track contributions too
– Though not necessarily a “form”, letters to the IRS for recharacterizations would be helpful
– 8606 forms would track when nondeductible contributions are involved, or when Roth conversions took place
– Statements for all accounts

Any other common ones?

And, can the data from one type of form be assembled by some combination of the other forms? What I mean is that statements might be missing, 8606 forms might not have been filed when they should have, etc. The W-2 forms, 1099-R forms, and 5498 forms stand a better chance of being kept because of having being generated by others.