Ultimatums-do they actually work

Tiglet2

Is one of the sellers called Jeremy?

Salemicus

Ultimata.  

nicmyles

Ultimatum worked for me in similar situation with divorcing couple. 
What others have said about just telling them you're looking at other houses is probably the more sensible move, but after eight months running up against a brick wall we found that emotionally we needed to draw a line under it ourselves as no progress seemed likely.
So we told them to exchange by the end of the day or we'd pull out, we did mean it, the EA believed we meant it, and they did it.
I think their decision was helped by the fact one of the couple had long since moved out with the kids, the house was mostly empty, and the other vendor had initially said he would go into rented before changing his mind, so we always had that to point back to.

Robbo66

They do if you are prepared to follow through with it