Just not worth it 
2005 Nissan Sentra Sedan 1.8 4dr Sedan (1.8L 4cyl 5M)
Get the warranty!
 This was my first car and I purchased the car with 23,500 miles on it. At 30,000 I had a problem with the starter hesitating to turn over. I kept up the expensive oil changes and paid for every service that was suggested. At 45,780 the check engine light came on and at 45,970 the heat went. I was informed by Nissan today that the engine has to be replaced to to a bad head gasket that caused several other problems. Thankfully Nissan is covering it but I'm seriously thinking of trading this junk in for another car. A blown head gasket at almost 46,000 miles!