This question was touched upon elsewhere but not really directly addressed. I want to buy an H2D, in fact I was about to pull the trigger. Now I see the H2C is coming out, which looks really cool. My questions are, 1) do you think the H2C will be cheaper than the H2D + upgrade kit? I really don’t want to spend more. 2) Will the upgraded H2D be the same as an H2C, or will the H2C still be more sturdy or have more functions? I know nobody can say for sure, but some people here have an uncanny ability to make good predictions about future printers.
Of course the H2C is going to be cheaper than buying an H2D and upgrading it that’s only natural. My personal opinion is the upgrade kit will cost $800-1000.
Will the upgraded H2D be as good as the H2C? Well it is supposed to be, if you put it together correctly and competently. But can a person put it together as well as a factory made H2C I don’t know that will be a challenge won’t it.
Honestly, even Bambulab probably won’t be able to answer these questions at the moment, simply because the H2C isn’t ready for production.
I’d wait and see what comes out at the end of the year.
I also expect the upgrade kit to cost between $800 and $1,000, and a similar increase from the H2C to the H2D.
And the conversion will certainly be quite challenging and not for someone who wants to do it in an afternoon.
I may be unpopular, especially with the many fanboys here, but if I have to spend €800-1000 and also lose 2 cm of print bed, I’ll keep my H2D as it is and pair it with a Snapmaker U1. 
Waiting for Bambu to make its real toolchanger… and not a gimmick designed to keep up with the times after realizing they had made the wrong plans… (my opinion)