Where can I buy AI tech?

Excuse me, I'm interested in investing in AI technology and I'm wondering where I can find reliable sources to purchase it. Are there any specific platforms or marketplaces that specialize in selling AI technologies? Additionally, what factors should I consider when selecting a seller or product to ensure that I'm getting the best value for my money and that the technology is of high quality? Is there a way to verify the authenticity and performance of the AI tech before making a purchase?