I have this exact same issue so I'll tell you what I have learnt so far from my experience.
You can take your ex to court to force the sale of the house, but this is a long, expensive process and you'd need a solicitor.
Your other option is to get him to buy your share of the remaining equity. Typically this is split 50/50 but if you are the main carer of the children then you should aim to get at least 60%. This is also a long process but not as long as a force of sale, I am led to believe.
Or, of course, you could buy him out but as I understand it, you want to move 2 hours away and you are well within your rights to do so.
As I understand it, any arrangement you come to will need to be rubber stamped by the court anyway, which will cost a hundred or so pounds. You want to avoid using solicitors for anything other than producing documents etc - not arguing, as this is where you could lose in excess of £10k.
You're best to sort out all the finances at the same time. Maintenance, pensions, everything.
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