plan to make double rail sliding doors for my house. so wanna ask the price around how much for 10' stainless steel or wrought iron sliding door.

gonna make my gate soon.. planning to make a double folding with rail gate. plan to make simple horizontal metal type powder coated black color.

a few questions..

1. roller/bolt/etc need to be galvanised or stainless steel? which one least maintenance if autogate wants to be installed in the future.
2. will my gate need to be repainted every year since its powder coated?

I got quoted price for a basic folding autogate system for rm2800. price include everything like hacking, motor, cables bla bla. all except the gate itself. worth it?