Hello everyone,
I'm currently thinking about creating my own click-and-point adventure and the problem I'm facing is the graphics. The visual style should be, if possible, something like Black Mirror( http://www.zockon.de...zockon.de-3.jpg ). Now I know how they've done it, pre-rendered high-poly models, but I have my doubts about whether I, as one person on his own, can get similar results(I only started with Blender 2 weeks ago) in reasonable time. What do you think, what should I do?

It will take a very long time. Notice how there's a lot of decals and detail to give things a natural 'wear', plus the realistic lighting and composition. If you don't have previous artistical experience you won't reach this level of quality within the reasonable amount of time you want. You'd also need texture libraries with that theme.

Keep in mind I said "this level of quality" - you will be able to produce something nonetheless.
I don't know what's your budget. If you have the cash to invest, prefer to hire an artist that you're sure can make that kind of work.