wotandbuy - Welcome to the TBN forum
i have so much to say, but i will try to be brief (you can send me a private message anytime).
1) you are a remarkable young man, and remind me a lot of my Son In Law who is about 5 yrs older than you.
2) I'm feeling a bit older suddenly,
being 58 yrs old... I have a brother in Australia.
3) I have had a physical disability since birth, and much of my life is compromised (balancing, walking, carrying items etc) ... I have Cerebral Palsy to a moderate / significant impact. (you can ask me, or google it to better understand that limitation). I am only sharing that because the tractor has been such a blessing to me. I do a fair amount of physical work and activity, it just takes me longer, and I need to be careful. The tractor aids in almost everything outside. Let me just say that I have a hobby farm and the tractor is my friend. There are times when one of my (tractor knowledgeable) friends stops by, and has no hesitation to assist me, especially if the tractor is out.
4) I considered all of those tractors, and am glad that my tractor - the Kubota BX23S actually made it onto your shortlist - mine is easy to operate and certainly saves me a lot of work. I have completed things that I could not have imagined doing without it. It is my first tractor ever. I love it. Kioti was my second choice actually - part of my decision was dealer proximity and my overall connection with the dealership.
5) re: mom's love for gardening - the tractor can do a lot of things to assist with gardening, and a small tractor can operate in confined areas. She may also enjoy having a Green House as another way of doing gardening and showing off her skills.
My first thought is to take your parents to a local / area Tractor Dealership and have them learn about the tractors, try out different features, to see what they like. There may also be used tractors to consider.
Perhaps you know a person with a tractor, a friendly farmer etc. to get further insight from.
There may be a way to get a short term tractor rental for a week or so, to check it out on the property.
All the best in your efforts to make things easier for your parents. This could be a fun time. Thank You for posting.