have you checked power steering fluid level? if it was low / just received and previous owners filled it up without your knowledge. you may need to simply move steering wheel fully left till ya hit a stop and then fully right till ya hit a stop. just repeat this a few times to help clear out any air that might be in the hoses / cylinder. then recheck power steering fluid.
other words air trapped in the system, and is causing the play, and ya just need to work out the air by fully turning steering wheel in both directions till ya hit a stop.