Its a difficult question to reply, as it starts by your oppinion on what is important and when.
But please allow me to add some "selling experineces" from some of the loyal and returning customers. In fact do we currently have 2 customers that have made a complete plan for their modifications including budget and timeframe, and asked us for guidelines.
Truely the very first customer owned Nikis Project cars.
Watch out, as one of them will be fast, very very very fast.
But in most cases does the modification list begin with improvement of the air intake and performance filters. Its far the cheapest and less complexed way to get additional power and torgue out of the engine, calculated per additional horsepower.
Second is it chip modifications.
First trip is already found here, as when getting the performance filter, do you need think in advance, and get a filter that is suitable for the outcome of the egine, once its chipped. Otherwise are both mods not working 100%.
Then does a lot of owners start looking at the body or suspension, disregarding an important engine issue - exhaust. Is the current exhaust suitable for the increased engine power? In most cases, no.
The exhaust issue is huge thing, as everybody has their own opinion in which brand is the best. I agree that the list is long, and finding the right exhaust is difficult. But looking at all of the options without any "bluring brands" are the real power increasing options very limited as very few brands actually claims that their exhaust adds power, and proofs it!
Ok lets say that all above is done, the car is fast and agile. And as it's an M3, will I assume that the OEM brakes are suitable for a while. Then do we need to look underneath the car, as suspension can be improved.
Springs, migt even lowering springs, shocks, sway bars, etc should be next step. Lowering springs for mostly visual purposes. Then maybe strut bars ( hot topic and everybody has their own opinion)
When done do we have fast, agile and very nice handling car - but it looks standard all the way.
Then do we do the body, by adding our own personal look to the car. Some does it very intense, others very limited. While being outside of the car, do we might want to change the lights.
Wow, now are we talking, but once inside, all the standard parts still inside.
Then it's time for steering wheel, pedals, mats, interior kits, etc etc.
It's a long list.
But the list begins at you, whats your budget and whats important for you to start with, and where to end.
I would recommend following starting list as it will leave some time between the expensive mods.
1) Performance filter
3) Some interior items (gear handle, pedals, etc)
4) Fist body mod, front spoiler or lights
7) Sway/strut bars
8) Next body mod, rear skirt or lights
Rims, either right now as rims still are on Spring sale in most shops, or during fall/winter (price dropping due to off season)
Some shops does offer volume discount, even over greater period, contact some that you believe in and trust, and negotiate with them.
If all others fails, contact me and lets work something out.
But watch out, I'm very tempting B) B)
You might end up with a streamer " Performed by Niki" and a rock solid driving machine