Should you invest $1,000 in Palantir Technologies right now? Before you buy stock in Palantir Technologies, consider this: The Motley Fool Stock Advisor analyst team just identifi

Palantir Technologies stock is pushing even higher on Friday after closing at a record Thursday. In Friday trading, the stock climbed 2.2% to $40.08, on pace to set another record. Shares of the provider of data-analytics software rose 4.

But that premise doesn't in and of itself make Palantir stock a buy. Valuation always matters in investing, and investors need to be clear about what expectations have been priced into Palantir's shares after their impressive surge. PLTR Revenue (TTM) data by YCharts.

Furthermore, Palantir's market cap has risen to $82 billion. A 100-fold gain in the stock would take the market cap to $8.2 trillion. This is about 2.3 times the $3.4 trillion market cap of Apple, the current market cap leader. That shows the extent of how much Palantir is going to have to grow to make millionaires out of small investors.

Palantir made great strides recently in turning speculative AI opportunities into real, revenue-generating applications. See why I'm rating PLTR stock a sell.

While Palantir has lots of opportunities in the AI market, there are two reasons I think Microsoft's stock is the better option. First, it's far less expensive than Palantir's shares.