Yep:
How does Scotty earn his pay and buy a boat? How does Kirk sell his house from Generations? With what does Uhura buy the Tribble from Cyrano Jones? TOS never bothered with that "there's no money" nonsense.
Extremely. Floating around in a space suit in a spacedock trying to build a massive starship from raw materials would be incredible difficult and insanely dangerous. You'd also need the entire construction staff to be masters of zero-G construction. You'd have a larger and cheaper labor pool doing most of it on the ground. Even Roddenberry imagined that the Enterprise was built mostly on the ground.
I could get behind building the major structures on the ground (as seems to be the case in the UP picture) and then assembling them in orbit but building the whole thing from the gound up on the ground? Don't buy it.
As for the money issue, it's a push on that one. It's always been my belief that some form of currency or payment exsists. It almost has too. But it would also seem to be a very different economy. The "cost" of building something "expensive" like a starship in orbit is probably irrelevant in Trek's time. Considering, again, how ingraned into society space travel is.
As for danger and risk, I again point out that spacetravel and spacewalking is very much an "everyday" thing in the 23c. It still certainly carries with it a danger and a risk but not as much as I think you're supposing it to be.
