I have been self employed all my life n run my own businesses, started with fifty bucks n some business cards. At one stage I was turning over millions a year but it took 16 hour days n 7 days a week in a high end/very large profit industry to succeed.
Todays economy is bad. Worst I have seen in 20 plus years. Insurance n public liability n super n various other costs are huge. You will spend less time with family probably for the first few years than u currently do now. Never walk away from a paying gold mine til it turns to a crap silver mine. If u are making decent $$$ now, I say stay n research starting the business part time on the side/spare time to dip your toes in the water first. Refinding employment if things don't work out if u leave could be a major issue in this current economy (it will take a few years to get better). I had a face to face talk with mining magnate Clive Palmer recently and he says things will get worse before better this next few years. (long story, my kid plays with his grand-daughter).
After 20 plus years of running my own business, I have decided to take a high salary job with a global company because I was bored of what I was doing after 20 plus years, but not bored of the money. Now, I will make less (but still great money) and I will have more personal n family time.
Its a hard one Blair, because only you know your savings $$ position and equity position of your property (or properties).
I have always been a go getter n thrown caution to the wind n in your own business the rewards can be huge, but the economy under liberal governments 16 yrs out of 20 years-ish made that a easier decision cause the economy was strong everywhere. The economy now is tough everywhere.
As u get older, u tend to errr on the side of caution. I say keep ya job, research your potential new business, make it work part time n prove it will be a winner, and then, only leave your safe financial position/current job.
You need a good accountant n a business which receives about 30 percent of its gross income in cash form. Never spend the cash on business items, only on personal stuff (and keep the cash business/amounts on the quiet ofcourse), then u might get lucky n have a winner.
One last point I want to make about self employment n gross income n profit margins.
My grandfather told me this when I was apx 16 years of age.
You can sell 100 ice creams a day n make $100, or you can sell the icecream machine for $1000 dollars n make $400 a day.
Always choose high profit margin over high turnover. That has been my success for 20 yrs. Also, only work with the top end of town (aim for rich people who have $$ to spend n don't quibble over pricing) n stick to the high end of the market. If u aim for the general everybody joe blow public segment of the market, they, the consumer will cut ya throat for $2 and u will be battling against ten other companies who have made the mistake of dealing/selling/working with the average $$ person.
Only aim for the rich n work their referrals hard, this way cashflow n profit margins stay high n u get to live well. Hope it works out. Hope it helps.