I had a place in the jungle in CR for about 15 years. Before building a house I hung a hammock between 2 guava trees. It was the dry season. Within a week I realized there was a 3 meter rosey boa living in a hole 20 ft away.
She(I think it was a she because 4 years later she bit my girfriend on the ankle) at first would go back into her hole when I came close(closer). But then we became friends and everyday at 4 pm she would be there and allowed me to sit within a few feet and talk. I was there alone and would tell her my plans as she was my only company. She would arrange herself so she looked right at me. Soothed by my voice.
I told some folks and before long a guy wanted to catch and sell her. I never let him know where I lived.
My point is that there are people who(illegally) will capture and sell big snakes. Maybe you can find such a person.
The snakes I respected were the terciopelos. Their heads are different than boas but the markings are similar.
I once found what I thought was a small brownish boa curled on the top-plate in the corner of my bedroom when I returned from work(hotel manager). I always carried a short, sharp machete which i used to touch the snake so I could see if it was a boa. Well, in a flash, I saw 2 tourqouis eyes and it struck at my face from 2 feet away and a foot above me. It got within 8 inches of my face as I took a half step back. Terciopelos are pit vipers and open their mouths 180 degrees. I got a good look at 2 white fangs on top and 2 black fangs on the bottom jaw. Not striking me and not wanting to fall from its perch the snake closed his mouth enough that he could see me. As he commenced a second strike I had cocked my machete and drove it through his neck , just below his head, pinning it to the wall. It did not even wiggle, it was dead instantly. Still stuck on my sword, I carried out onto the deck and flung it back into the jungle, roaring like a wild man.
All I have as proof is a photo of the wall with blood dripping down from a machete hole.....
Boas are good.
Terciopleos are bad.