Designing Kitchens and Bathrooms - Window above bath sink - replace w/ mirror?

My wife and I are getting ready to make an offer on a house that we love. We have one puzzling thing we have not been able to figure out how to remedy:

There is a standard size window directly over the bathroom sink. We would like to put in a mirror or medicine cabinet with mirror.

Not sure what the best/easiest/cheapest way to do this. Have thought of relocating sink, but thought this may be much too expensive and too difficult to tackle ourselves.

Any ideas?

paint the window from outside to make it a mirror (just kidding). Place a mirror on the window is the cheapest way I can think, or take out the window.

well other than the other guys joking remarks you would need to remove the window frame,insulate and drywall,and repaint or paper the bath not a major on that side . The biggie is the outside depending on what the home is sided with. Wood,vinal,brick,ect. if its wood how much of the home will you have to repaint? If its vinal can you sill buy the same color and brand and if you can how bad is it faded and will it match? as for brick well same thing how well will it match. ? is it located on a sside where no one will see these things or is it on the front where everyone will spot the patch????