I am looking at setting up a Limo buisness, can anyone give me any tips on best practice in starting up?

I am looking at getting 3 x Milleniums, a Black, a white and a Pink as these seem the most popular and gives customers a nice choice.

I currently am Hackney Licenced, but looking to widen our field somewhat and always fancied the Limos as a second string.

Any help, greatly appreciated