Do sellers carry out due diligence on buyers?

I have read a few cases recently and did a note to self 'make sure I never get involved with those cowboys', as you do! Anyway, I see masses of questions (pre-qualification, tender etc) from buyers to sellers (much of it not necessary but that's another story), but how often do sellers carry out some sort of due diligence on their buyers (at any level of the supply chain)? What is the legal status of the actual company I might enter into contract with, what sort of reputation do they have, what are their payment records to sellers, maybe something on culture, and so on? I bet people are wary of doing this, thinking it might 'upset' the buyer but that's tosh. What do people think, how frequently does this sort of check take place?

Rob