Thanks very much for this extra information Geoff. Yes, this looks like the law we are dealing with. Using a conversion I found on the internet (
Convert Euros (EUR) and Greek Drachmas (GRD): Currency Exchange Rate Conversion Calculator) the 5,000 Drachmas converts to EUR14.67 per metre, which is the same (less a Euro cent) than the figure Michael quotes. I guess there could have been amendments in the detail of the law since 1999, but this is a great start.
We are heading off cruising for a few weeks now, so won't do any more on this for a while. We will post if there are any developments.