What exactly is an annex / outbuilding?

Hi all, 

we have an opportunity to buy a piece of land (olivetto) that has a 30 sqm annex / outbuilding on it which is classified as a C/6 building.

For the last 10 years, the previous owner has used this as a weekend "house", built a kitchen in it, a small bath and toilette and a very small bed room.
It has power, water from a well and is a real stone structure.
But is is not a residence.
When we talked to a geometra he basically told us that all of this is not legal.

The question I have is the following:
What can you technically do with an annex / C6 building?

I was told that in the past, many of the these outbuildings have been used for the farm workers to have their lunch , etc.
They were not always used just for equipment but many times farm workers also stayed there during the work period.

So what is possible there?

Can you have a small bath in there?
Can you have a small kitchen in there?

What makes an outbuilding technically a residence?
The geometra pointed us to Article 10 in some document that describes rules for outbuildings after November 13 1997

We are thinking of using this on the weekends to just be there, cook, relax and be close to nature.
Our other real house is about 4 miles away but doesn't have the space to have a garden, plant vegetables, etc

thanks
Markus

A C/6 is not an annex.  Its a stall, stable, garage.   You cannot live in it, at least not legally.   It shouldnt have a bathroom nor kitchen.  
However if you choose to live in a shed, then its your choice.
You can possibly change the destination to residential if it has all the requirements, height, light, services.  
But it would need permissions, and be costly.

thanks for the reply, there are other issues with regulations in Umbria, to convert an annex / outbuilding / stall into a residential  building, it has to be within 50 meters of other houses and has to be built before 1997 (which our is).
I am just trying to understand what defines a residence as a "residence".
If I can't turn it into  a "residence", what stops me from making a stall or a stable or a garage really nice with a kitchen and a bathroom so I can spend the summer afternoons there?

It comes down to what turns a stall into a residence and what does it mean to live in it?
Does living mean sleeping in it?
Does living mean the ability to cook and use a bathroom?

Is it a residence when it has a place to sleep?
Is it a kitchen?
A bathroom?

Or where is it written that a stall or a garage is not allowed to have a kitchen or a bathroom?

thanks
Markus

To be a residence it must have services, (kitchen Bathroom) have legal minimum height, and legal minumum light and ventilation (windows mainly).     A bathroom from scratch requires permissions - sewage and water, and therefore the  genio civile.     
The seller has put in a bathroom connected to what? Waste water goes where?  Water comes from a well - is the well legal, does it have permissions, has the water been tested etc -  Then for the comune the question is - a C/6 is now a house - why are you paying IMU on a C/6 when it should be reaccatasto and become a house with the consequential rise in rateable value.  
Or you close both eyes and do as the locals do, but can probably never sell it.

"If I can't turn it into  a "residence", what stops me from making a stall or a stable or a garage really nice with a kitchen and a bathroom so I can spend the summer afternoons there?

Probably nothing at all - just don't try to sell with it as anything other than a stall/stable [probably best to remove kitchen/bath before sale]