Can buyers have more than one payment term applied to their account?

Yes, multiple payment terms can be applied to a buyers account. Please see this article on apply payments terms to a buyer account.

*If multiple payment terms are applied to a buyer account, they will then have the option of which term they would like to choose as they go through the ordering process. If you would like to control the specific option that they have, it is advisable to only apply a single payment term to their account.