I've heard RVs go to goose Island or a nearby truck stop. I travel in an SUV.

I have filled up at the marina before but it can be busy and hard to access the water at times. Locals are nice offer to pay to fill and have a nice conversation. I have done both

I would recommend going in to Port Lavaca and go to the state rv campground at Lighthouse Beach. It's $10 for dump and includes water. Best of luck!

Picnic area by the beach. Otherwise there isn't much in the area.

There is a water source right on the beach. There is a public restroom and picnic area on the beach that has water