The VAT clause is often relegated to boilerplate status, and isn’t really considered until and unless there’s a problem. By that point it’s often too late. Reimbursing suppliers' expenses can be dealt with several different ways, with different VAT effects. Beware the unclear VAT clause in this context, because your boilerplate may not match the parties’ intentions. Having upfront agreement between the parties, and a properly drafted VAT clause before you start, can save a lot of trouble later on.