Risk taking is one thing - jumping into a major trunk splitting operation on reasonable pre-bonsai material without ever having tested the technique on true throw-away material first just seems kind of reckless.
As is, I'd consider this a pre-bonsai that requires about five years of work to get it moving in the right direction, but I know that in that time it would start to look like a decent tree. Splitting that trunk is likely to turn this into more like a 20 year project, and you'd have to get lucky and not have it rot or die back as
@Brian Van Fleet mentioned. I think I'd save the trunk splitting project for some beanpole collected tree that doesn't otherwise have any trunk flair. And if I were serious about it, I'd try it on at least a few different trees so that I could judge the results across multiple instances. After a few years of seeing how it responded, I
might consider trying it on something more valuable, but only if the crappy tree turned out OK.
I get wild trees that show up in my yard every year - ash, zelkova, linden, elm. This sounds like the kind of thing I might try on one of those. That way, if it doesn't work out, at least I didn't spend any real money on the experiment.
As for the value of this tree ... well, that's going to be very subjective based on who you ask and what they see in it. For me, I probably wouldn't pay more than $75-100 for this, but that's because I see the most value in the base. I'd let it grow out and try to build a crown out of it, but the fallback plan would probably be to chop above that first or second branch and re-grow from there. But either way, that's a lot of years of work to get it to the state I like my trees in, so I wouldn't pay a premium for that reason.
That said, I could easily see if somebody was really into the pad look, or happened to like the style of the trunk as it is, that this would look much more like a finished tree to them and they might pay more, maybe even significantly more. I wouldn't be at all surprised to see at least a $200 or $300 price tag on this, I just wouldn't personally pay that for it. But I'm also the guy who digs around for hours looking for deals on nursery stock to grow out instead of buying trees at the bonsai shop, so I'm probably a
lot fussier than most people would be. All I see is a decent trunk base that's already had the root work done. =) Please take my pricing comments with that in mind.
