Basically any vessel that is large enough and can be sanitized properly can be used as a fermenter. Here in the states, Home Depot sells 5 gallon food grade storage buckets for about $5.00, look around in Germany and see if any of your big box stores sell food grade buckets. They will usually be white and have a big label on them stating that they are safe for food storage. Grab a locking lid for it, drill a hole in the lid for the air lock and you can have a fermentor for about $8.00 or so. You will need two to split the batch up if you are making a 5 gallon brew though, not enough head space otherwise. But still, $16 for two fermentors is not bad.