I have started about 10 businesses during the last 30+ years and have loved every day. All have been profitable. Start-up costs ranged from $0.00 to $240.00. There are few things more satisfying than making a nice living from a business that you created on a zero dollar investment.,,,,,,,,,,,,,,,, and then doing it again....... and again.
I have always specialized in contrarian mentoring based on finding a niche and exploiting it. This avenue is not for most as it will usually go against what most people say, and everything you read.
If you do what you love, the money will follow.