The difference, say, between a US 250 Canon 50/1.8 LTM and a > 7k US 50 Apo Summicron is not crucial at all, when you consider output.
As long as a lens is good enough, nobody will be able to tell the difference when looking at your photo.
However, it's a whole different story to shoot with a camera that you like vs. one that feels cheap, unreliable, etc. How I feel clearly impacts my photos, as it should.
Also, compared to their modern DSLR counterparts, unless you look at Russian lenses, all Leica mount lenses today are expensive. 300 dollars and up is not cheap.
Roland.
PS: looking at your other thread, denizg7, I would also never cheap out on a scanner 🙂. It's one of the pieces in my flow with the most impact on results.