I don't think funding is an issue. Those that backed the game obviously funded a good preportion of it but I suspect the company publishing the game for normal retail will also add in money to the pot. Probably had to pay a few million to secure the rights and then pay royalties on the number sold. The important thing is Shenmue 3 exists because a huge chunk of development costs were funded by kickstarter backers.
As for development costs I would of thought using an off the shelf development environment would massively reduce those costs. Shenmue is no longer cutting edge and Sega had to write its own development tools but not here. There may be existing resources from the earlier game that will be improved and re-used for Shenmue 3.
All in all its looks to be in a very healthy financial position for developing this game which I think is the most important thing of all.
