Hello and welcome! Lot’s of questions here and a lot of this just depends on several things. First off, if you want to collect it I’d suggest trying to get as much root mass as possible. I would wait until early spring which is proper re-potting season to to dig it. Place in a tigh box with sifted pumice and check out the Randy Knight Aftercare Mirai live stream-it’s full of great into on aftercare for collected trees. After you collect, you don’t want to work on the tree for 1-3 years, your goal is to get it nice and healthy before any styling. If you collect it, the great thing is you’ll get some valuable experience in collecting/aftercare.
Is the tree worth collecting? Well that depends on your goals. Often when you just start getting into Bonsai, it’s good to practice your horticultural skills, collecting, aftercare, wiring/styling and grafting. Will this tree be a show winner? Here’s the negatives- trunks are fairly straight, not much taper in the trunks, the foliage is pretty high, and not much interesting natural deadwood. However, you could think of this as a tree to learn from and practice with. To make anything worth while, this will involve creating jin/shari and grafting foliage closer down on the trunk, this would be a radical change.
If your not looking to invest that much time and effort into humble material, than you could always pass and look for better options or start something from seed/cutting/airlayer. When your just starting out, it’s important to get your hands dirty and learn. That way when you find that incredible Yamadori years from now, you’ll already have the experience to extract and care for it properly. Cheers!