Hi,

Your first, and most challenging 'barrier' is yourself. Examine your motives, your reasons, and your resolve. You will need to make some hugely challenging changes in your life, how you relate to your family and firends, and how you use your time.

Other 'barriers' can include your competition, your local market(s), market identification, and other mechanical considerations like financing, resources, labor, etc.

Good Luck!

Source: http://www.abusinessmentor.com