I feel your pain, 17 years for me also. It's the lawyers more than the Ex - they tell them that they are entitled to half of everything. Going thru it myself and received legal advice, is yes, 50% after a long marriage irrespective of who put what into the kitty.
You cannot even make a private agreement with the ex as it has to be approved by a judge to be legal and final - more kerching for the lawyers, even more if you challenge the judge.
A lot of the Judges who do Families & Divorce are women, as are a lot of the lawyers - many with a burning anti-men split in their past. First thing they say to a divorcing woman is that he will try to hide his assets and lie about his income. Sets up the agro nicely for later..kerching.
Disposals have to be at market rate, proof of this that and everything, plus extra for the kids future education ('course they're going to go to college,) or the unsatisfied Judge rejects the agreement until their "recommendations" are included.
Depending on her lawyer, they might argue you can sell the van and buy a cheap 2nd hand one to keep earning the maintenance. That actually is do-able, your tools are worth f.all. Instead she'll have half plus, of your savings and any private pension plan.
My Ex is being very reasonable and blew the lawyers out, but I've still got to find a big wedge for her, but she's leaving my pension alone. Most of mine was earnt before we met, but apparently that don't count with the judges. I've bought her another car and luckily she is still working with a decent wage.