Hi Jan,(posted 8282 days ago)Some answers - hopefully others can contribute too.
1. Her liabilities. Unless the mortgage says otherwise I expect she is jointly liable for it irrespective of what her solicitor says. For example, if the property was sold at a profit, she would no doubt expect a share. Your partner needs, repeat needs, to go and see a solicitor to get some quality advice. It may well be that his ex cannot afford to contribute to the property given she has responsibilities elsewhere - for her own rental and also to maintain the kids.
2. Handing in the Keys. Dont. Try and sell it. My absolute advice is not to hand in the keys, particularly as you don't mention any arrears. Provided he gets some advice he ought to be able to offset any payments he makes singularly against her share of any profit made from the sale (if any). Equally, if the property sells at a loss, he ought to be able to reclaim a percentage from her or again, at least offset it from any alimony payments. If the keys are handed in, the lawyer sharks will go for whoever has the most money irrespective of the fairness or otherwise of the situation.
3. The Kids I am also divorced and I have two kids. It is worth thinking about before taking any action against his ex - like sicking the building society on her - because anything bad happening to her WILL ALSO affect the kids in the same way - so if you improverish her, you make them poor too. Is that what he would want?