Cheap Arduino for a beginner

And what do you mean with "beginner"?

New to electronics?
New to micro-controllers?
New to the Arduino family?

An Uno R3 is something like 30$

If you want cheap, you can get an ft232 board for 3,55$ and a pro mini clone for 2,93$
..... But you will have to solder. How much of a beginner are you?

If you are a real beginning beginner, I would recommend saving up for an original Uno R3.
Then you know that it will be working correctly, and you can start learning.