I've had the extreme displeasure of working on several 'farm use' ebikes this season and don't recommend them at all. They are not built for the hard use/abuse they will encounter.
The ones I worked on were used daily and ridden through the fields to get where they had to go. Because of this, and wet, muddy fields, the moisture, mud and manure infiltrated the battery box...no battery box is sealed enough to prevent some sort of intrusion under these conditions...and corroded the connections ruining the battery. To make matters worse the owners did not bother to hose down their bikes after use and just left them wet, muddy and manure covered until used again and then complete failure.
The bike brand refused to warranty anything declaring use beyond the 'normal' use of said ebike. We agreed...
The bike owner blamed us...of course...and we eventually had to ask him to leave the shop and not bring us any more bikes...he did not buy the bike froam us.
We no longer work on bikes in this condition...he never bothered to clean off the sh i t when he brought it to us, expecting us to...we did and charged him for it.
I suggest buying a gas powered mini bike or other small motor bike. They are, in the long run, more dependable and far easier to get parts for.
We are finding it more and more difficult to find the correct replacement parts...electronic parts, controllers, batteries, etc....for non bike shop ebikes...meaning internet purchased...We have decided to no longer perform any electrical/electronic service on any internet purchased...meaning non bike brand ebike...ebike that comes our way. This will have an impact on our service but honestly we lose so many hours searching the internet for parts for these crap ebikes that we lose money on every service repair as we find it difficult to charge for the time spent searching for parts that generally no longer exist.
Good luck with whatever you do...