From the interview with Walter Vezzoli in today’s Il Fatto Quotidiano: “Before I start: the article talks about a resort that doesn’t exist and isn’t even meant to exist. My dream was to create 30 homes that are energy-wise self-sufficient with purifiers that recycle rain water and with solar panels. Wind mills. A dream. It’s just that I’ve never found the money for the investment and thus all that is left of the village is to be found among the papers of some companies that are still active and of others that have closed down. Today’s newspapers are pointing me out as the man of the anonymous companies abroad, but I was living abroad. My son grew up in Costa Rica and I was the owner of a discotheque: where would you expect me to register the companies? Apart from the fact that I don’t have a cent, but there was no money to bring to Italy under the “Fiscal Shield” legislation. Because I was working there and I had different activities. Beppe Grillo? He’s never been to Costa Rica. Beppe Grillo’s investments? But what are we talking about? I’ll see what’s to be done and I’ll have a look to see whether I should bring a legal case for defamation. But the resort that l’Espresso is talking about does not exist. It has never existed. I went to look at 30 hectares of land and my thinking was that 15 of those would be for building. But I didn’t even buy one metre.
"Armonia Parvin", indicated as the mysterious company and perhaps connected to Grillo. It was a shop selling organic products measuring 20 square metres, then it was closed down as it wasn’t making a profit. Parvin is the name of Grillo’s wife of Grillo, but the owner of the shop was Parvin’s sister. It’s possible that she simply liked the name."

From the website "Ecofeudo.com": "In the era of stress and pollution in the cities, the project EcoFeudo proposes a model of life immersed in nature and well-being, but at the same time, offers high technology and maximum comfort. EcoFeudo creates a strong synergy between comfort and nature, between technology and environment. We offer homes in harmony with the Earth’s equilibrium of the world, of high quality and innovative design. The construction of each residence uses low-consumption technology and with zero impact on the environment that completely offset emissions of co2 into the atmosphere."
Tip for the journalists of l'Espresso: refer to Wikipedia and find out that the meaning of an “anonymous company” (Sociedad Anónima, abbreviation: S.A.), in Costa Rica and in nearly all the Spanish speaking countries of the world, is something like that of a “Società per Azioni” {joint-stock company} in Italy.
Checking sources: Costa Rica stopped being a tax haven in 2011. This is the OECD list of countries that have substantially implemented the internationally agreed tax standard recognised by international bodies. The list includes Costa Rica together with other states like Italy.

You could find these posts interesting:

Thank you Espresso!

The freedom of the press is precarious

De Benedetti challenged in Ivrea