The financial services royal commission has heard Suncorp may still have some unfair contract terms in its dealings with small businesses around 18 months after they were banned.

The commission also heard National Australia Bank insisted on taking the proceeds of a business customer's home sale despite having "no lawful entitlement" to do so.

That is among other instances where small and medium businesses have been bankrupted or sent to the brink of collapse by the banks' handling of their loans.