Glad you enjoy Detailing enough to want to do it as a business.
It can eat you alive if you get in over your head so be careful.
Have you considered finding out here for example, how many Detailers live close by to you, and see if perhaps you can Intern with someone for awhile?
It would have to be way less expensive than taking those classes, and you get to see what it is like on a day-to-day basis if you took time out to go do that.
There are a zillion questions you could ask a good Professional Detailer and we are not even getting to hands on working with a great Detailer yet...
Everything Mrclean81 said above here, is so true...
It is all Preparation work that should be completed before going full on into this business...
It would also be a great help to have another source of income going on to help you get started the first few years too... This is even more critical if you go out and lease working space somewhere.. The lease payment comes every month no matter what...
It cannot be the type of work that consumes you completely because it can if you allow it or make choices that are not the best for you.
Then, it will be a job you dread every morning... You dont want to ever let it get to that point...
Ask as many questions as possible... Get some face to face time with some really good Detailers, and learn, get a feel for how its working for them, try to understand how that set of circumstances would be for you in your particular situation, and learn all you can from other's experiences...
One does get wiser as one gets older, unless one is a complete idiot, etc...

There is so much to discuss, good luck with this !
Dan F