Not a smart idea.

I wouldn't do it, unless you have lots of money you don't mind having to part ways with sooner or later, lol. If I remember right, the M-Series models are built by hand by small teams of guys in Germany, not on a massive assembly line like their more generic 328i's, etc. They have their own unique parts, which are slightly better made than the regular cars. Only slightly. They're still not great quality, they know if you're buying a $70,000+ German car, you can afford the upkeep. Given that the M-Series replacement parts have limited demand, they're going to cost a fortune. 

Just a second thought, mental exercise for you, if you will: … if this is to be your "daily driver", and a BMW, … and an M model to boot: … why not just lease a ‘21 M model Beemer and be done with it?

I’m convinced, this will turn out be a much cheaper option, … more convenient, more fun: … a virgin car to start with ( not someone’s second, or maybe third discard), a full warranty, free road side assistance, courtesy loaner during frequent break downs (always a new-ish model BMW), zero totals invoices for all repair and service.

Compare that to the "used 2004-ish BMW M3”:… a lofty purchase price to start with (that is, if you locate the best of the bad rest), expensive regular service, expensive and frequent repairs (parts and labour, towing costs), prolonged and frequent rentals of replacement daily transportation (awaiting for replacement parts)

… anyway, did I say "Most horrid, … horrifying thought" earlier?

Best,

F.S.

Are you feeling lucky?

Most horrid, … horrifying thought, … stop it!

F.S.

I would not purchase unless you plan to work on that vehicle yourself (maintenance and majority of repairs), know where to get parts, are really familiar with how the mechanical and electrical systems on those vehicles work (almost to the point of being consider a pseudo-BMW mechanic), and have money set aside for the repairs (it will be expensive).  (YouTuber LegitStreetCars comes to mind). But, otherwise, pass on it.  Owning older German cars is a labor of love and not for the faint of heart.

I just so happen to get an E46 M3, 2003.5, for my first car as a daily driver… I ABSOLUTELY LOVE IT! It’s absolutely a nightmare at times especially if it wasn’t well taken care of. Mine I knew was going to be a project but it was just a dream of mine to own it. Parts are pretty pricey and I wouldn’t recommend working on it yourself it’s pretty hard and you’ll need a lot of special tools because well they like to make things difficult over at BMW. However I love the car, it has put me through hell, but i love it! Definitely have some money set aside for repairs, I had my smg pump go out so I converted to manual which was expensive. Anyway I would totally recommend if you don’t mind having a bratty child on your hands, but I truly love mine and I wouldn’t trade it or the experiences I’ve had with it these pat 2 years for anything. Amazing car, if you did or do get it you’ll love hearing it scream down the highways!! Good luck

The M3 is an amazing fast powerful vehicle. And previous owners run them hard. Harder than your usual car. 

If it were a regular BMW, I’d say maybe. But whoa with an M3, unless you know what you are doing, and willing to take the time and money for upkeep and repairs, look elsewhere. 

Also to add onto my other answer, don’t buy the “automatic transmission” it’s actually a sequential manual not a true automatic. No clutch but you still have to take your foot off the gas and use the paddles. Really fun transmission, but it’s really sketchy and can break at anytime really no matter the age of it. Just get a true 6-Speed i learned to drive stick in mine when i got it converted!