Like Anders says the Maxidiag is one of few tools to see the fault codes. You can flash any of the maxidiag models to read the Renault with files from the manufactures web site. So if there is another model going cheap then it is worth it.
http://www.ebay.co.uk/itm/maxidiag-/320948203968?pt=UK_Diagnostic_Tools_Equipment&hash=item4aba00f1c0Otherwisw put the money to a renault clip interface which will give you live data.
http://www.ebay.co.uk/itm/maxidiag-/320948203968?pt=UK_Diagnostic_Tools_Equipment&hash=item4aba00f1c0the links are just examples, i have not bought from these traders. I do have both & the both serve a purpose. The clip is not genuine it is a russian clone i'm told. You will need a small software file to run on any non approved laptop & a crack so it does not attempt to register itself with spx. Let me know if you go this route.