Buying and Selling of Real Estates and Condominiums in Germany:
Every sale of real estates and condominiums in Germany require generally that every owner declares his consent for selling in front of a notary. This can be done if all registered owners of the estate or condominium appear personally at the notary signing the sales contract or if one owner has a valid notarial power of attorney for selling the named estate on behalf of the other owner(s). The third possibility is that one owner signs the contract without power of attorney of the other owner. In this case the notary will sent the deed to the second owner asking him to approve the sale within 2 weeks; the approval has to be declared in front of any notary so the second owner has no obligation to declare his consent in front of the very notary who closed the contract. The sales contract becomes only enforceable on receipt of the approval.
Power of Attorney:
Even if a power of attorney or the approval of a sales contract generally can be declared in front of any notary in the world it is highly recommendable to chose a German notary or let the procedures done by a German consulate, which has the same legal effect. By choosing a non-German notary, your declaration needs a so called "apostille". This apostille is issued by the national high court certifying that the notary who signed the power of attorney or the approval is lawful established and according to the national legislation entitled to issue such papers. You can imagine that these apostille-procedures are time- and money-consuming and therefore not recommendable.
If an owner dies, ownership of an estate or condominium is legally transferred directly to the heir. BUT the German land register has to be corrected. The heir has to apply for correction with a German "Erbschein" (certificate of inheritance) which is issued by the German probate court and costs time and money especially if foreigners are involved. Without the Erbschein there will be no correction of the land register and in general no possibility to sell the estate because the heirs cannot prove their ownership . The procedures will not be much easier if you should decide to set up a will in Germany.