Re house signs:
There are certainly local regulations about putting up signs, and while they do affect villas for rent, I don't know about private houses. I could find out for you.
Are you now in Corfu or in UK?
There is at least one man in Corfu town who does beautiful painted metal house signs, and on the main Paleocastritsa road, a couple of kms past the Tzavros road junction going northwest, there is a lovely pottery. The man there makes house signs amongst other things and he is very cheap.
If you want more info on this, send me a private message and I can enlarge on it without boring everyone else!