Buying a small piece of land from a neighbour

Assuming that you own the house, ask the notaris who acted for you when you bought it. However, I suspect that the costs involved in buying a small piece of land and transferring it from being part of one property to being part of another will be high compared to the actual value of the land. It will not be a simple case of buying a piece of land; you will be changing the format of two properties which will have implications for the national land registry, the commune, the taxes and so on.

You need to speak with your notaire. What you're proposing is a "modification de lotissement", which probably needs permission from the commune.

When we bought our house we discovered that the seller had exchanged the effective (but not registered) ownership of two identically sized parcels of land with a neighbour so that that neighbour could, as you wish, build a driveway.
It was the intention of both parties to regularise the situation as part of the sale process of our house but this proved impossible because there was a mortgage on the other house and the mortgage provider refused to accept the changes (even though they had increased the value of the other house because it had gained driveway access to the back garden and the compensatory land parcel that had been lost was a better fit with our garden than theirs). Our notaire had predicted that the mortgage provider wouldn't agree and, as an alternative, drew up a formal agreement giving each party the sole rights to use the informally transferred parcels of land. This, apparently, wouldn't survive a change of ownership, but such a change would, of course, give an opportunity to formally complete the transfers. Apart from the mortgage provider's objections, our notaire had foreseen no regulatory difficulties in registering the transfers and had anticipated that the tax implications would be minimal.
The land "swap" meant that no actual money changed hands but the neighbour who gained the driveway met (and will meet) all the costs including fencing.
In your case, I might suggest that a starting point for valuation of the payment to the neighbours would be half the increase in value of your property that would arise from gaining a driveway, plus the loss in value of their property, plus all their costs.

I propose having a friendly debate regarding the purchase with your neighbor first. For a sense of cost, look up comparable land prices in your local real estate listings. Seek advice from a property surveyor or real estate attorney to make it lawful.sso login

I suggest having a friendly discussion with your neighbor about the purchase first. For an idea of costs, check local real estate listings for comparable land prices. Consulting a property surveyor or real estate attorney can ensure everything is legally sound. This approach can lead to a smooth and informed decision. https://y20india.net/ilgms-citizen-service-portal-kerala/