This is of yesterday, You can stay for free on the 'dirt field' but there is no cover, I didn't inspect the field. I was enquiring for covered secure parking which in amongst the other cars just outside the terminal (covered). If you go to the parking office (not in the terminal building) you can become a member for a year for 400 baht, then it's 2,000 per month, so for example in my case 6 weeks is 4,000 baht.

This time of year that field turns into a gigantic mud filled area after the rains.  It would not be where one would want to park.  I used to park under the covered Area towards the end of the parking lot when I lived there and we would travel for 2 to 3 weeks at a time.  Cheap as chips, instead of leaving the Triton parked at home where god knows what might befall it.