'One gear single speed bicycles at a very reasonable price'

I found this on gumtree:

http://www.gumtree.com/london/15/58421615.html

I wouldn’t keep it like this for long, new saddle, pedals, toe straps, bars, I just have a small student budget to go on and this is ready to ride.

What are people’s thoughts on these as a first complete bike?

Thanks, Smudge