I find it odd that your wife's parent are even considering agreeing to staying in your small flat with you, your wife and a new baby! They must be aware of your circumstances, and your one bedroom. I appreciate that your wife wants to share this time with the baby's grandparents, and of course, she should, given that they live so far away, but surely she would agree to them staying somewhere else close by, spending days with the three of you and the nights somewhere else? Could your family help with accommodation? If not, and depending on your relationshi[p with the in-laws, perhaps you might have a quiet word with them and see if they are really happy to be squished into a tiny flat with two new parents and a tiny baby every day and night for 2-3 weeks. You might find they may be more accomodating than you think, given the circumstances! Good luck with the new baby!