short answer, Move.

there is no such thing as no corporate life forever. when you start your business there's always politics and competition internally and externally

What is important for you. having more free time but takes many more years to fund your business? or work hard for 5 years in the new company to fund for your business. assuming no change in lifestyle you're saving 5k saving per month that is 60k per year, by 5th year you have 300k good to start up a business.

having flexible time is not an excuse. I think its best describe, you're comfortable with your current work schedule and lifestyle. but you're still complaining low wage, which is why you're fishing for opportunity. But once you got the pay you want, you're questioning whether you should leave your comfort zone. Which triggers you to question your reason to reject the offer.

There is no such thing as losing time. you plan for your business accordingly. if you cannot cope with the workload and timing, hire another worker to carryout the work. with 5k you can probably hire a fresh executive or a diploma experience worker to run your business chore.

no worries mate. When everyone sees success in entrepreneurship, they think its easy and rosy. what you see online are the very little percentage of successful people. However there are a large number of people whom failed and never disclose the world about it. some lost their life long savings. some sinked in endless debts. there are even those i know, owe ah long, ran away or committed suicide. You might ask, eh, why would they resort into borrowing ah long? when your business sinks hard with endless pit but trying to keep it afloat, you got no avenue to take up loan or borrow money. at that depth of debt, you would usually face issues on committing repayment, resulting in low CTOS and CCRIS scores. No banks is willing to show mercy. While AKPK may facilitate in restructuring, you're taking years or decades of hardwork, just to climb out of that nasty hole. In no way i'm scaring anyone, but I'm giving an heads up the difference between self employed and being employed. being employed, you'll always know by 28th or last day of the month you will get a fixed salary. For self employed, not so. and if you have subordinates, good luck if you do not get enough profit to pay for their wage. Your workers can report to the authorities after the 7th of the month and you will get into major trouble.

My advise, start the business when you know you can run full time with at least 1 year without salary and cashflow to keep the business afloat. if not work in tandem, its very very hard, but its one way to keep your business funded by your primary daily job and insured that if you drop the business, you still have a host to rely on giving you a monthly $$.