sharpness

[raba]

can someone tell me how to render a professional interior so everything is sharp?
the room is about 7x7 meters
how important is the render size?

[Micha]

It depends on your final needed size for viewing. At the www you can find tables with dpi and print sizes. Attached an old screenshot I use.

And fi you like to get more sharpness than you could disable the Antialiasing Filter.