I would agree with Vivid Color.
At this point, which camera model is the least of your worries.
In the photography business, there is a lot of work that needs to be done, and almost none of it has to do with the actual taking of the pictures.
Good luck with it, but don't get in to debt on the chance that your business will be successful.
As part of structuring your business plan, ask your self this question:
"why would anyone hire ME as their photographer, instead of the hundred (hundreds) of other experienced professional photographers?"
If you, as the business owner can't objectively answer that, how can your potential customers answer it?
Good luck with it. In my opinion, the last thing I would want to be is a professional photographer. That's a tough way to make a living and an easy way to ruin a hobby.