Hi Ainef
You're far from alone in this position.
However, borrowing a further €280k is not really a runner on your income - you would end up with debts of roughly 7.5 times your household income.
Is there any possibility of porting the tracker on your current home?
Alternatively, you might need to rent somewhere more suitable for a while and build up your savings. I suspect your husband's rental property is killing you financially and it probably would make sense to get shot of that ASAP.
Whatever you do, run the figures and take your time.
Best of luck.