What default is best when viewing Checking & Savings transaction history in bank to answer bank customer questions? 90, 60, 30, 15, 10 days, since last statements, All or other?
Do you expect the default to be different between Checking and Savings accounts?

What you can have probably depends on your system and memory issues. And it could depend on the questions your customers normally have and how easy it is to retrieve the information. There probably isn't one-size-fits-all or a recommended default.

Our DDA screen shows transactions since the last statment, since customers should have (Ha!) reviewed their last statement to see what has paid and balance their checkbooks. We have access to prior statements on our screen also but most questions are about current transactions.

Savings transaction screen shows transactions since the end of the prior year. Do we really need that much? Don't really know but we only "purge" savings transactions once per year for savings.

Since last statement is what I typically use... otherwise it is a mess viewing 60 days worth of debit card transactions while trying to find out if check 1234 cleared.