Hi there,
It's an unfortunate situation you're in, and I'm afraid the lender has the right to say what they are saying, although I am somewhat surprised by it. Can I ask who the lender is?
As for your options, they are exactly as you have said.
From a long term perspective, property prices will probably rise again in the future, although no necessarily as quickly as you would hope.
If you are planning on staying in the property, say for the next 10 years, you will probably find that the price has risen and you are no longer in negative equity. But you have no real option other than maintaining the mortgage as it is, ie in both names, and waiting for prices to rise again at which point you can transfer the mortgage into your name at a smaller cost to yourself(or hopefully no cost at all). The other option is to pay the lump sum as requested.
However in this case, it seems to me your ex partner should be responsible for half of the negative equity amount.
Assuming the property is jointly own equally, there is no reason you should be forking out for the lump sum negative equity payment.
If that isn't clear, let me put it another way.
Suppose you sell the house, you make a 16k loss, the mortgage is in both names and you are both liable for the 16k. Not just you.
Essentiall if you transfer the property into soley your name, you are buying the property from both of you (weird way of looking at it, but that is the case). So here, you are both selling the entire property to you. So why should you take the entire loss?
If there is 16k needed to make up the difference, you should both pay half. And if your expartner wont pay, then say you will simply sell the property and then he will be forced to pay anyway.
If you need to speak this through with someone, speak to either a solicitor or an independent
mortgage broker. As this may be easier to explain over a conversation rather than via me rambling on in this forum.
Hope that helps a little, and if you have any more questions either contact me direct for a free chat or post any questions you have on here.