What does building an outdoor kitchen in Isaan cost?

There is nothing to say about the way you ask the question Arie.
By next to the house do you mean a lean-to on the house or separate from the house?
Make a sketch and walk into a hardware store.
Layout of pantry square meters with or without walls glass or doors lighting ceiling tiles yes or no and so on.
You usually just pay for material on your own account, work for small self-employed persons separately.
Here, the hardware store simply brings it home or the small self-employed person collects it himself.

Also coincidentally, just had a part done, I well I my love has arranged everything so that I stay far in the background .. usually saves a few pennies.

So did part of the outdoor kitchen last month including

– soil raised approximately 30 cm over a surface of 5×5 meters
– covering on one side against existing wall steel net posts in shotcrete blocks filled with cement opposite the house wall at a distance of approximately 4 meters
Steel load-bearing beams and cross-beam roof made of galvanized iron, so to speak, made of corrugated sheets

– Cement finishing floor
Water connection drain connection to existing drain main drain

The roof has an overhang of approximately 1 meter over / beyond the cement floor and approximately 2 meters to the house on one side and therefore measures approximately 8×6 metres.

There was already about half of the ground and all the gravel and sand, so we had 2 or 3 trucks tipped and there was enough to raise.

We have a stainless steel kitchen unit there that we already had

What has not (yet) been done so far, finishing stucco tiles etc etc fixed masonry and tiled kitchen

What it cost us
2000 baht ground
14000 baht material and construction

Best of luck!