Nigella,
YOu are looking at 10-15k for a fully represented Final Hearing(on top of costs to FDR). You can keep talking all the way up to it to try to settle. The main costs come when the bundle for court of prepared and the barrister does all their bits .. this is usually in the final week before the hearing.
If you are only about 10-15k apart at FDR then it is worth trying to compromise. If it is more than that - and you really feel there is no chance of settlement - and are certain you are being fair and reasonable in the face of the opposite ... then sometimes a FH is the only way to go. I have mine soon. I hope it will be a wake up call for stbx

. He has cost me nearly £30k so far .. is being completely selfish about his "needs" .. and ignoring the fact that I have the kids .. and he has not - and will not - pay anything towards them

. The name says it all ....
Hadenoughnow