WANTING TO IMMIGRATE

Hi, my father immigrated to South Africa from Germany many years ago.  I therefore have a German passport and so do my two children.  My husband is South African.  We are wanting to relocate our family to Germany as we cannot see a future in South Africa anymore.  We honestly don't know where to start as where to live.  Our children must attend International school where they can be taught in English but also learn German.   As far as I'm aware my children and I require no documentation to move to Germany as we have German passports.   My father does have property in Germany which we could stay in but it's in a very small village and it does not make sense to move there as they have no international schools.  I would appreciate any advice on where to start looking and any information on what we would require from a documentation and financial point on view.  My husband will not be working in Germany, we will be financially secure but require information on what the Government require from us.