Hi Feena, we have a 2006 318i in the family. The thing about BMW is that they sell you a dream. They will be no more reliable than average and worse than many. Our one has failed twice with coil pack failure, €200 fix. This is a very common failure on the petrol models this vintage. Diesel models also have a lot of potential issues, worst one being ingestion of some parts into the internals, expensive fix, potential new engine.
That said it is a good drive and comfortable and of course you do have that badge on the bonnet. A 2005 could be E46 version or later E90, if you don't know the difference I suggest a little more research. If E90 look for steering wheel controls and rear parking sensor options... Our SE spec has sunroof and leather which is nice to have as well. Good luck.