If you can settle things amicably and wait a while to divorce then you can miss out on solicitors fees. After 2 years, if both parties agree, you can do the papers yourself and only pay the fees. It used to be something like £250 for the decree nisi bit and then another £60 or so for the absolute. The time taken depends on how busy the courts are but once you have your nisi, it is then 6 weeks and 1 day before you can apply for the absolute. This comes through in no time after that.
If you wait 5 years then you don't need the other parties signatures, but the timings are similar.
However, if you are in any doubt as to the financial arrangements, then I would recommend a solicitor to get it all in writing - especially when it comes to money for the children and how much and how long he pays for.
When you do the divorce papers, you will also have to do "statement of arrangements for children" this sets out how often and how long he will have the children - so weekends, holidays etc.
The other thing to do is a Clean Break Order, this means that he will not be entitled to any future money you inherit etc. It is often overlooked (I never did one) but it is a very good thing to do, especially when things are likely to be acrimonious.
Hope this helps somewhat. You have my best wishes hun. It's a rough time for you. xxx