This might depend on where you are. In my area, it's unusual to have to provide a retainer at all unless you're doing something big or the lawyer suspects you might have trouble paying your bill later.

In my personal experience with small firms closed ended matters like wills, contracts, or individual IP filings don't require a retainer.

Open ended matters, like probate, starting an IP portfolio, or response to a C&D trigger a retainer.

> bootstrapped startups from underprivileged people.

i dont think startups should be paying a retainer. You do this only after it's worth the money - ala, you either know your domain is a gray area and is definitely going to require a lawyer.

This has nothing to do with underprivileged people or not.