For sure a normal thing to do. Of course only do it if it is the car you want.
I have a bunch of friend who are mechanics an have saved me from buying cars that either need lots of work or have a high cost of maintenance. After all said and done I purchased a car I have been wanting for a long time. 2010 a4 avant prestige Sline fully loaded with 22k on it but it's the car I want too.
If you have any doubt if you want it or not then don't get it.