Ive posted about this before but a quick background is this:
Was with abusive (in every sense but mainly emotional) XH for 12 years from the age of 17, he was 25. We married in 2013 but he cheated (again) shortly after. I got legal advice (free half hour) and was told short marriage, no entitlement. I was advised to move out and the best I could hope for was a clean break where we each left with our own debts. The house we were living in at the time was my childhood home, sold to us at a large discount by my parents. There was a small mortgage and I signed a document saying I would not pursue any future rights to the house. acting on the advice I got at the time, we did a diy divorce and ironically I let him divorce me on the basis of my infidelity. I moved into private rental, he stayed in the house. We've both moved on to other relationships now but he's proven to be very difficult over maintenance and the children (7&5).
So, I went to see a solicitor today and I've been told the initial advice was wrong and I should have been told to enter a charge against the property and that I should have been advised I could pursue up to 50% of the equity. This solicitor is saying I can try and do that now, starting with mediation.
However, I know that XH will hit the roof, is unlikely to pay for mediation and will fight me for the entirety of the house. The solicitor fees are extortionate (£300 just to start the case) and I'm not guaranteed anything at the end.
I'm not sure what to do or how to proceed. I'm having mixed emotions about it all from anger at my first solicitor to fear at rocking the boat now - I wasn't exactly happy that he's taken my childhood home whilst I got nothing but I thought that was what a court would decide anyway so more or less accepted that.
I would really appreciate some advice about whether I pursue a lump sum to represent my contribution to the marriage (and I do feel like I made a huge contribution supporting XH through job loss and retraining, raising the DC single handed whilst he pissed his wages up the wall and slept about). I guess I'm asking what would you do in my circumstances? A lump sum would provide a deposit for a proper home for me and the DC, otherwise I'll be saving for the next decade.
TIA 
P.s. If anyone is looking at getting divorced, please see lots of different solicitors. At the time I was upset and angry and didn't have the emotional energy to seek other advice but I'm now hugely regretting that.