A stock market crash may seem like a disturbing event. But it can also offer the savvy long-term investor a great opportunity to buy world-class companies at a low price.

By doing this, I think the next time the market crashes I could realistically aim to operate £35,000 to build a portfolio that will eventually be worth £1 million. But waiting for disaster may be too behind schedule – I need to prepare now.

Getting money for investments

£35,000 is a significant amount of money and I would take the time to save it. It’s also more than a year’s worth of additions to my Stocks and Shares ISA.

So I would now set up a Stocks and Shares ISA and start putting money in to have £35,000 ready to invest in a tax competent way.

Please note that tax treatment depends on each client’s individual situation and may change in the future. The content of this article is for informational purposes only. It is not intended to be and does not constitute any form of tax advice. Readers are responsible for conducting their own due diligence and obtaining professional advice before making any investment decisions.

How would I aim for a million

So how could I aim to turn £35,000 into a £1m portfolio?

The key in this case would be to adopt a long-term approach to investing.

Imagine I invested £35,000 and this amount grew at a compound annual interest rate of 15%. After 24 years I would be a millionaire.

The challenge is that a 15% compound annual growth rate over the long term is much more arduous to achieve than you might think.

I operate the breakdown to my advantage

This is where the idea of ​​a stock market crash might come in handy. It can create opportunities to enhance my long-term profits.

Take an asset manager M&G (LSE: MNG) as an example.

If I were to buy the so-called FTSE100 shares, I would receive a potential dividend rate of 9.8%. This is already promising and places the share in one of the highest yields offered on the FTSE 100 index.

But let’s go back to a few points during the stock market crash in the spring of 2020, when M&G was selling for about 54% of its current price.

This means that if I had invested in stocks at that point, my investment would be now giving over 18% per year.

Making the right move at the right time

I happen to own M&G shares. I like the asset manager’s focus on a gigantic, vivid industry, its established reputation and client base. The dividend is attractive, with the last enhance announced just last month.

On the other hand, a company must work challenging to prosper. There was a net outflow of customer funds (excluding the company’s heritage business) in the first half, which could have hurt both revenues and profits.

Still, I plan to keep my shares in M&G. But if I had bought them during the 2020 crash, I would be making much more money on them now.

These opportunities may be short-lived, so it’s essential to be well prepared. I keep a purchase list of stocks I want to buy if I can get them at the right price.

I don’t know when the next stock market will crash. I think by preparing in advance I enhance my chances of turning £35,000 into a £1 million portfolio!