Sorry, I found nothing via the search, but that could also be due to the time and my tiredness.
Go to the forum search, with the term:
Barthel and from:
11ant - my usual linking service is currently inactive because I recently became aware that even internal links break here after recent changes :-( In summary: everything about newly developed building areas has already been described in this thread, my tips focus mainly on neglected properties, and there I advise approaches off the mainstream: your friends are called divorce lawyer, undertaker, nursing service, choir director, fire chief, etc., and last but definitely not least, realtor; and do not restrict yourself to such plots where the seller already knows that he wants to sell