Why not just buy SPY? The expense ratio is only 0.09% and it's one security to track.

Given $1000 to invest, I can't fathom trying to individually own an average of $2 worth of each of 500 companies. And that doesn't even begin to cover it. Because the S&P 500 is market cap weighted, you would need to own $45.70 of AAPL, the top company. I don't know what the 500th stock is, but you'd probably need to own about $0.10 of it.

Even if trades themselves are "free", you still need to pay something like $0.13 per trade in SEC fees. So you are paying about a 100% commission on each of the smallest stocks you buy. And then another 100% commission when those stocks fall out of the index and you sell.

Just buy SPY. There are many good reasons that it has grown to $307 billion in net assets.

There are robo advisors who will buy the individual securities in indices for you, as long as you have enough invested with them (50k? I forget). But the only advantage over simply buying the fund AFAIK is being able to tax loss harvest from the higher volatility of individual securities. Eg, if your two-security index has stock A go down 5% and stock B go up 6%,an index fund would simoly go up 1% while the actual basket would allow harvesting the losses from stock A.

As far as I can tell, this is a fairly minor advantage, and if I wasn't using a robo-advisor, i certainly wouldn't be managing the basket directly just for this ability.