EVSE doesn't allow flow in both directions but the wire going to your panel from it sure does. Not much equipment is needed. <$100 total from the electrical aisle at your local hardware store including a $20 lockout. If someone is setup for a gas generator, they basically already have what they need. The lightning works just like any generator. Don't need the $2k-$10k "setup". You welcome to opt for it though.Highly doubtful as your current EVSE will not allow flow in both directions.. and that's just for starters.
The equipment alone will easily be over $1,000-$2,000. Yes, I'm sure you can do the labor yourself if you know what you're doing... but it will need to pass inspection too, so it has to be up to code.