Howdee. E36M FTW.
Well, an E46 Coupe is definitely a looker. IMHO, a car will be more reliable if:
- It is newer, relatively speaking. So buy the newest car you can afford. This is a 2005/2006 model year.
- It has been well maintained. Even the newest E46 is going on 8 or 9 years, maybe 100K. Look for documented services like the cooling system (all of it), crankcase ventilation valve, routine oil and filter changes. Look for an OCI of better than factory interval of 15-17k miles.
- You engage a good indy to conduct a thorough pre-purchase inspection. Expect to pay a mechanic an hour or two time to check out any prospective purchases.
- It has fewer / less optional equipment. For example, no Navi, no fancy electronics, no sunroof, no accursed automatic transmission.
- It has been owned by an enthusiast owner. For example, look for cars owned by BMW CCA members, or posted for sale in the club magazine, Roundel.
Good luck in your search.