I did note that he was using 12.5 HP, WITH little or no problem… reminded me of when I was regularly using my MF65 /loaded tires and wheel weights, to pull a 6000 gallon water tank that I rigged up to wet the roads before graded them… That tractor did the job WITH little or no problem also. However had I a larger tractor I could have done that faster and safer with no problems.
When pulling a load, larger and heavier is the best combination.
When you want to do it faster, just add more horse power but increase the larger/ heavier.
Your point about dealer support I think is also a very important consideration, maybe the MOST important… This fellow sounds like he has been doing this in Costa Rica for a while, at least long enough to realize it is slow and tedious. …
What make tractors are your neighbors using? After all that is why in farming country you will see nothing but green or orange or red or blue or whatever tractors… check to see what the neighborhood is using… they are getting some type of support to keep working. Have fun KennyV.