The more market research you can do the better, if you are just going to sell bits then prices, competitors, customer base/numbers, shipping costs in and out, packaging costs etc, advertising/promoting, tax( :evil: ), storing the bits, etc etc
Consider who you are aiming to sell to, this might sound daft but eg if you only want to sell gt3rs tuning bits there are only a low number sold each year and they are spred across the whole country so instantly you have given yourself a very small customer base and altho most of your customers will be able to afford most things there will already be a fair amount of other businesses offering what you offer not to mention Porsche themselves (and seeing as they have the heritage and they developed the car people will pay obscene premiums) so already unless you have a one off/outstanding product for sale or are selling at mega cheap deals ur gona struggle or have a very low turn over and have stock sitting for ages if bought in bulk(risk of becoming obsolete)
the best thing you can do is to either aim at a big customer base, (eg ford) or offer things that arnt manufacturer based. (seats etc)
or find a product or service that is rare/amazing. If the product is good it will sell and word will spread.
If you are planning on doing this as a 2nd job it could end up eating away at your life before you even think about seeing a profit.
If you are doing this for your love of cars you could find yourself hating them VERY quickly!!
It can be a very good idea to go in with someone as this halfs the load/risk/stress etc however it can also turn out to be the worst thing if things go wrong (or well and they try and screw u)
so be very careful if you choose this avenue.
If it all takes off and works dont get greedy as it can destroy you much quicker than you could ever imagine
if this sounds negative im soz i dont mean it to be, i wish you all the best and anyone that goes for it full respect from me
with the way the world is now its never gona b easy but if you can do it now you will b laughing if anyone ever manages to sort the place out
anyway il shut up now but u may get a pm when my fingers can type again :lol: