[NicoR44]

Hi Vodka,

First of all it's a nice chair!
But you need to increase your poly's it's jacked now
I would use a nice leather on the seat with a good smooth bump and maybe a glossy map

I also think you need to use less d.o.f. so increase your dept of field

That's it for now, this should keep you busy till your next render

[Sheik]

There is no simple way to increase the poly count in SketchUp. Some parts you could just redraw, like the wheels. The FormFonts stuff will mostly work as part of a scene, but are not really ideal for close-ups, which imo is ok considering the low price.
I happened to have a higher poly similar Eams chair, so I rendered them both for comparison.

Nice carpet you have there, but the chair seems to hover above it.
Sheik

[Sheik]

I don’t know of any that are in SKP format, but you can import models as 3ds. They sometimes will need some cleaning up and texturing etc.
The problem with importing high poly furniture will be in the performance of SU; a few chairs will be no problem, but filling the whole room with them can slow down SU considerably.
You can find furniture at places like:
http://www.turbosquid.com/3d
http://www.evermotion.org/
Sheik