I won't say to much here as it may come across a bit biased. But some words of advice may help you decide in which direction you may wish to persue your business. First of all you need to decide in what end of the market you want to be there is a big difference.
Cleaning: This generally is right at the bottom and fairly simple require very little investment and with the right work can make you a descent living. What will set you apart from normal cleaners is that you need to understand the problem to solve it. As a Example a company calls you in and wants there floor cleaned. Now the big question is but you have cleaners?! Well they can't do it you should have the knowledge of why they can't shift it and also have a good education of the chemicals you use.
Light Restoration: There are a lot of these guys about being able to restore any floor pretty much. Here is where you start to get your teeth into the art and certainly will make you hungry for more most importantly it's rewarding finacially and results you will achieve. Here the investment in equipment will become higher. Typically though you will bond together your knowledge of cleaning and parts of restoration to get your results that others can't. What counts here is the quality of materials you buy and being able to think on your feet. But inevitably you will come across a few that you can't do! as sad as it sounds this is the point that you walk away as you go wrong then it will go wrong! or you become ridicusly addicted to it!
Before you go any further than this stage I would advise if not already to get yourself on a tiling course just so you understand a bit about substrates and will now how to do
tile replacements.
Restoration: Well this is everything you will be able to fix any problem, your getting to the top of your game competition is minimal at the moment. But the expense of equipment can be £££££ there is also a lot more that can go wrong which can cost £££££. This is where you start to get challenges whether it me a plain white marble to a polished concrete floor. When I first started I used to find it boring but the more you learn, the more problems you encounter the better it gets for me anyway!
Anyway I hope this helps you
Tony