What can you do about an ex who is dragging his feet in settling up?

I received this via my fb page and am soliciting advice here before responding.

“I am a single parent to four children. I moved out of our family home due to domestic violence 12 months ago. I have been renting a house and the children reside with me for 85% of the time. The issue I am having at the moment is my Ex is taking his sweet time to decide if he is going to sell the house or keep it and pay me out. I am getting sick and tired of this game and want to be payed out or the house on the market ASAP. How do I go about this? Do I have to see a solicitor? I really can’t afford to pay one at the moment. Can I send him an official letter demanding that it is put on the market within a certain time? Thank you :-)”

What do you guys think?