It's up to a business owner to retain records, not any accounting platform. Data can become corrupted, software providers can go out of business, software versions can graduate from fully-supported status, subscriptions can expire, laptops can wear out. For each year, export the Reports that are suggested on the Export data screen, and all lists, as a start. These will export to Excel, files will be in a compressed format. Backup on your laptop, make sure files can be read. Then copy on a few thumbdrives, put one of those thumbdrives in a fire and waterproof location. If other reports not on their list are your "go-to's" or you have customized reports that you love, export whole-year versions of those, too.
Gear > Export data
Work through Reports tab, then Lists tab
Because your main concern is regarding payments, here is how to customize a Transaction Detail by Account so that it has the same information as a Cash Disbursement report. Export this report to Excel, add it to those thumbdrives.
TRANSACTION DETAIL SHOWING CASH DISBURSEMENTS
Reports > Custom Reports
Search for Transaction Detail by Account
Choose appropriate period
Group by account.
Click Customize (upper right)
Choose these columns, for starters, add others that you find to be helpful:
Type, Date, Num, Name, Memo, Clr, Split, Amount
Filter by these Transactions (click all boxes)
Check, Bill payment, Paycheck, Liability payment, Sales tax payment
Run report
Save customization so it'll be there for next time (upper right)
This report will have one account as a heading and the other under "Split." Other Cash Disbursement reports have two or more lines with affected accounts under a single check number. Grouping by Transaction Type and Sorting by Num will get a result that is closer to a more traditional Cash Disbursement report.