To get started, sure. To last, no. I started and sold two businesses - 1 retail, 1 services. I wouldn't dream of starting another (this one trading anyway is my last) with less than $100k.
Well that should stop you going out of business due to an initial drawdown. You then need to make sure you have a valid edge that is profitable, otherwise you are doomed to fail. Assuming your edge is valid and you can be profitable. Stocks are not highly leveraged like futures or options. So high returns like 100% or 300% are harder to achieve with stocks. 50% might be more realistic from stock trading. But thats only $15K a year. Even if you can make 100% it is only $30K..
$30k is fine if he has several years to compound the account without withdrawing anything. Otherwise, it's too little, barring some incredible strategy that lets him >5x in a year.
as stated in a previous post, I also own an insurance agency, so the income is not an issue. My intent is to build up the account to the point where, at some point in the future I may be able to live off the income from daytrading.
Why a business at this time? As a business won't data fee's etc be more expensive although they can be written off. What is your time line for being able to live off trading income?