You can take the test as many times as you want, it usually runs for $160 each time. But remember the tests are days a part from each other, so lets say you give a test today, you will have the result in three weeks or something after the test and of course depending on the result you will decide to sit again or not. If you are not satisfied with the result, you have to register in another test which may be another few weeks after your results. So total time may be 2 months between two test or may be more depending upon the test center.
