What should I consider when choosing solar street lights for a residential or industrial project?

I’m looking into solar street lights for an outdoor project in Pune, Maharashtra. There are many options available, so I’m trying to understand what really matters before choosing one.

Things like brightness, battery backup, solar panel capacity, installation, maintenance, and overall life of the light seem important. I’d also like to know whether an all-in-one solar street light or a conventional setup is better for long-term use.

If anyone has experience installing solar street lights for societies, industries, roads, or similar projects, I’d appreciate your suggestions on what specifications I should check before buying.