There are accountants listed on this website that will be glad to offer proper professional advice, but I can have a quick stab here:
-- the current rate of CGT on property sales?
As I understand CGT as a concept does not really exist here, so you pay regular tax on your profits as income, although the sale of some assets (e.g. retiring from your business) gets only taxed on 50% of the profit.
http://www.germany.info/relaunch/business/...ital_gains.html-- whether, if not resident in Germany when the house is sold, one is still subject to CGT in Germany (can the capital gain be reported elsewhere?)
As a general rule property is taxed in the country of its location. So 99% sure that even if you lived overseas (e.g. Monaco) and sold a German property that had been held less than 10 years - you would still get whacked by the Erics.
-- whether CGT is levied in the context of overall multi-year income or is considered as a single, one-off item? For example, would it be possible to 'stretch' any large CGT payment across the years between purchase and sale when no income has been made in Germany -- so as to stay within a low tax band?
CGT does not exist here. So when you sell the house and make €100,000 profit in that year - it is taxed in that year as regular income.
-- whether the 'no CGT after 10 years' rule is up for revision... I read that it is rumoured to be reformed at some point, but when?
They are looking to go for a 25% CGT tax in 2008 or 2009. But I dunno is this will be directed at properties, and I also doubt that it can be backdated. So would assume it the new tax would apply FROM the new date of 2008, and any profits AFTER that date would be taxable - i.e. any increase in the value AFTER that date would have the new tax. Otherwise would be a total impossible drama with people that have owned places for 30 years having to sell up very very quickly!!!