I do not know nearly enough to advise you with certainty. However, a few pointers :
1. You are much better trying to resolve this matter by negotiation if possible. The more money that goes to lawyers, the less there is for both of you, and more importantly, for your kids.
2. child maintenance
is calculated by reference to a fixed proportion of the net salary of your husband and therefore there is little or no room for negotiation. Try the CSA website where you will find a calculator which will give you at least a general idea.
3, In addition, on the basis of the information you have given me, I think that spousal maintenance ( ie for yourself ) is at least a possibility It is very difficult these days, even for an expert, to second guess a Court and what it might do. But you cannot rule this out ; even if it is not much, it all helps, and it can be varied upwards at a later stage if your husband is earning megabucks 10 years down the line.
4,Liza, I think you would greatly benefit from a visit to your local CAB for advice about benefits. These can be very important in low income cases. In particular, in your case, I would be thinking of the possibility of housing benefit ( help towards your rent ) and Council tax benefit, to help with your Council tax. The problem that I find here is that it seems to me that, even if you got the whole of the proceeds, you are unlikely to be able to buy a house for yourself and 3 kids. So I think you will at least have to consider renting, and the problem here is that any capital you have can, and in your case probably will, affect your claim for housing and Council tax benefit.
5. As regards the house, I admit I just don't know. You do have to remember that a Court will have to consider your husband's needs as well. This is a situation which seems to me to call for creative thinking on both sides, to see how, by a combination of various means, the needs of both of you can be met. I can think of several possibilities, and what your solicitor has told you about the possibility of a horse deal is certainly one option. There is, I am afraid, no getting round the fact that divorce means a lowering of living standards all round, for both of you. I think you will need some more legal advice ; for a start, you can't really put the house on the market unless you are agreed as to what happens to the purchase money. But go to the CAB first and see what they say.