I agree with what everyone has said so far. Start-up cost can be tricky and what I mean is you have to determine if the cost is worth you getting involved. You have to believe in the people operating the company, the products or services or combination of both, the business plan, and etc.
Business is not truly about money but more about helping people with a need. Money is just the end result or reward for doing so. Now yes there are some great companies out (old and new) there with little start-up cost which is good today. I started for $49 and yes most have an operating cost. Look at it this way, if a business was free - would the masses get involved? You can say yes and no. Because free means some would see it as being undervalued and others would see it as a great opportunity. Some would not work it seriously. But if you place the pricetag at $500 most would not want to blow that type of money.
Find the passion, find your cause, and the money part will not matter. Sucess comes from working towards a goal. With a passion that goal becomes easier to work towards and you will not quit.
And always do your due diligence on the company, the ceo , the president, the market, and especially the upline chain. You do not want to join an organization when you have the person leading to be a person that jumps from companies.