How can I invest £99 a week to aim for an income of £94,095 a year for life

Whenever I have spare cash, I invest in companies within my Stocks and Shares ISA. Ultimately, I would like to live off the income from this portfolio.

However, this is not a get-rich-quick scheme. I have to be patient.

But the good news is that small amounts can add up to surprisingly large amounts, given enough time.

Passive investing

One of the easiest ways to build a portfolio is through low-cost exchange-traded funds (ETFs). This allows people to invest in multiple stocks, bonds, commodities, and more, in one swoop.

Many UK investors gravitate towards FTSE 100known for its stability and great benefits. The long-term annual average is about 8%.

However, it is true that many world-changing firms are listed on the other side of the pond. Their products dominate our daily lives, whether it's iPhones (an apple), entertainment (Disney again Netflix), Facebook and Instagram (Meta Platforms), or a Google search (Alphabets).

I S&P 500with its significant exposure to technology stocks, it generated an average return of nearly 10% (including dividends).

Income opportunities

Let's assume that I invest passively in both directions and the historical returns remain broadly the same (not guaranteed). So that's 9%.

In this scenario, I could end up with £1,159,308 after 35 years of investing just £99 a week (not including any platform fees). And that starts from the beginning!

At this point, I would use the 4% withdrawal rule. This would see me take down £46,372 a year.

Active investing

Instead of just investing, I decided to take an active, stock-picking approach. This is risky and time-consuming, but the potential rewards are enormous.

Axon Company (NASDAQ: AXON) is a good example of this. The stock is up almost 1,300% since my first investment in 2017. It has been an amazing long-term winner and is now at its peak.

The company has already gone from selling Tasers to becoming a major public safety technology platform. Today, its products range from body and vehicle cameras to cloud-based AI services and drones.

Most police in the US and UK now wear Axon body cameras (for accountability and evidence gathering) and Tasers (for safety and a less lethal option than guns). This is Axon's recurring revenue contract.

However, the wider international opportunity for both products remains huge. The market penetration rate in Europe, Asia, and Latin America is basically close to 0%!

In Scotland, the police, lawyers, and courts all now rely on Axon's integrated evidence database. The concept has enormous growth potential if other countries (larger than Scotland) move all their justice systems to the Axon platform.

Of course, all this opens up issues of data privacy, which is dangerous. And the stock is far from cheap today.

Heading up

I wish all my investments produced Axon-like returns, but the truth is I bought duds.

However, the math is skewed in my favor because the potential gains from higher stocks in theory don't add up.

• Axon Enterprise: +1,300% (so far)
• Max loss from dud: -100%

Even if I managed to return an extra 2% on the S&P 500 (so, 12%), that's enough for a portfolio of £2,352,389. In terms of income, it equates to £94,095 a year.