New Easter Egg?

[OneOverAstro]

I believe I may have found a new easter egg in France. Not sure what the signs mean other than it's a property for sale and the land size. Also not sure what those digits under the "750m²" thing mean. The only reason I believe this to be an easter egg is because it was playing that one electronic song at this location, similarly to other PM easter eggs. Anyone got any further clues? Let me know.

[ScuL]

I'm not sure about there being an Easter Egg there but if the music is playing there might be something hiding. The "for rent" sign has a phone number on it

[OneOverAstro]

Oh ok. I guess the phone number is not something I'm used to as an American because the only two phone number formats I'm used to are the old xxx-xxx-xxxx and the newer (xxx) xxx-xxxx.

[ScuL]

In France they use dots for phone numbers

[RonaldLewis]

Tolles Osterei! Ich verfolge oft die Ereignisse dieses einen und suche nach verschiedenen Ostereiern, übrigens, Sie können eine Menge verschiedener Ostereier auf reddit finden!

[YounyCorn]

Hi, I'm french, and try to reach this number.

When i call it, it appear that is an old version of an electronic gadget : "tatoo number" (https://fr.wikipedia.org/wiki/Tatoo).
I don't know how to proceed next ^^'