The decision is a tough one, but you will not likely be successful opening a part-time shop. It takes full dedication for most small businesses to have a chance. You would be better off working double time at your current job and save enough money to live on for 2-3 years after you quit your job (also enough to buy your inventory). Then throw everything you have into your new business. This is what I did when I went into business for myself many years ago. I put up with 80 hour work weeks at a job I didn't like, so I could put in 100 hour work weeks as a small business owner. Without the 14 hour days, 7 days a week for a few years, most new businesses will fail.