[blunte]

Indeed as a candidate, I don't want to waste my time either.

Your clients know their budgets. Why not just be upfront about that to the candidates. Tell us your budget or reasonable expected range your client can pay. Then if (when) we find that it's well below what some other hungry companies are paying, we can save you and us time by passing.

If you know your client is paying low, then just be open about it. Something like, "Ok, this client is a bit below market (and tell the upper limit they will pay), but they have these good things to offer." If the client has no good things to offer, and the pay is low, then you're still likely to not seal the deal with a candidate no matter what. So just cut the game and get to the point.