Need to paint the new tilt garage door (steel) and the new timber jambs, probably the porch fence (metal) as well. The garage door is west facing so it receive a lot of UV, especially in summer, so weather and UV resistance may be a major consideration (it doesn't show any sign of rust).
Questions:
Should I use different paint for all 3 types of surface? Assume yes (all in deep ocean or similar colour).
- Weathershield seems to be for exterior (wall, etc.)
- Metalshield - seems to be the best option for outdoor metal, works for both the garage door and fence (tried dulux metalshield epoxy enamel to respray door handle the oily smell lasted very long, but it shouldn't be a concern for outdoor parts)...
- Acratex - acrylic as top coat for the garage door (overkill)?
- The exterior paint on top of the rendered external wall showed some mould buildup over the years (cannot be removed), thinking of giving it another coat - weathershield matt / low sheen or something else that can last longer (Resistant to UV and mould)?
- Any additional sealant on top of the last coat?

Any advice will be appreciated. TIA