RedMidge

You do not need to purchase property to obtain  residence.  But, you will need to show financial stability and health coverage. And this is even before Brexit!  After next year's Brexit,   we still do not know what will happen. Maybe you will need to apply for a visa as  Non-EU citizen.

Having lived in Australia, and visited NZ- not sure if I would choose Germany to move to with family of 3 children! Lovely country- also visited before the earthquake, so have seen the contrast.  Aussie friend was always amazed at the "clean sheep"! But, it was too far while parents alive.  I do like Germany- so much to visit, culture, and would always stay up here near the sea. Whatever the decision- wish you well!

Good that you have family here to help.  Many of your questions and issues will be difficult for them to answer. Many Germans have no idea of problems many newcomers face with things like health insurance, car insurance etc. They take them for granted ! One family member here was amazed that we had to pay so much for Krankenkasse! Have to say that health care here has impressed me.( Speaking as RN) Good idea to get a letter from auto insurers- with amount of claim free years.  

OP has not indicated what profession/ job he has. Maybe he is transferring from company in NZ, or maybe has job lined up. Has Op done an exploratory trip over to Germany? Might be a good idea, maybe set up some interviews. If this is all just prelim research, then good to find out early. OP - check out things like Health Insurance,  Driving licence reciprocity, moving costs, think about a holiday flat to start with. May be able to negotiate a 3-4 months rental while home searching. Any large dogs?!  Can be a deterrent for landlords. Good luck.!       

  Sounds like a job for the  TT Gurus! Johng and Starshollow are Insurance experts who advertise on TT, and always get great reviews !!

Disaster- missing piece!!

Just do not hyperventilate about this!

I just went into Forum-looked at thread for visas, and they are all listed in most recent date. Except the first few- which have been pinned.  

A nice easy and cheap place to live for a couple of years. Time to move on!

Had visitors who were blitzed, their own car, and letter followed them to UK home. 

Maybe the mother will be able to get pensioner's health covered by NHS in Germany. But the OP/ daughter will need own healthcare, no job lined up and plans language classes. Unless they have a deep bank account to cover all expenses, this might be a tough move.

  Are you talking "Squatter's rights " here?! If you really have been contributing to household expenses, and have all documentation to prove this, then maybe you can negotiate a longer stay.  But, if ex wants you out- Dad will back her.

If this problem is not cleared up correctly, the little   terrors will re-appear.  If they are coming from another unit, then  others need to be treated.

OP- have you read the UK Gov. website- specifically  "Moving and living abroad", "Moving to Germany"? OP says they will have no job, so how will they  acquire health coverage?  May apply for Public- but not cheap.  Cost of  renting a place to live? Swimmer is correct-  if 80 year old mother is covered by UK NHS, then what will they cover? Will it be capped at what  NHS would cover in the UK?  Would German health expect  her to pay extra for Pflegestufe? Insurances will not come cheap when age factored in, What happens after Brexit is still a mystery. 

What is the old saying about guests and fish? AS your relationship is over, this might be stretching any goodwill her father has left.    Get proactive and  move out. Get a holiday flat, room - anywhere, but   unless you have a contract and paying rent...!