I installed 5 pieces 3mm solid polycarbonate shade with aluminium glazing bars and painted mild steel frame in 2001 at RM22 psf. Lightweight and strong, keeps out sun and rain. Still in use today. Polycarbonate shade is still good though the mild steel frame is a little rusty here and there due to water leaks after a few years when the sealant cracks. There is also some dust/algae growth on the shade.

You need to remove the old sealant and to reseal after a few years ( standard no leak warranty 1 year only ) and to clean the shade. You can always hire some Indon workers to do resealing and cleaning. You can D.I.Y. on the cleaning part. I use bleach to remove algae and a pressure gun to get rid of stubborn dirt.