We would red tag that in my area it would have to be in a protective sleeve like an oil line has and be clamped to the wall whare the regulator is for support.
other then that you did a grate job for florida
we use the conical (looks like tip of a rpg) caps on vent pipes. Need something on vent termination if only cheap screening wire. Regulator would need to be run horizontal or at least the drip leg before regulater would have to tee down. Regulators are ok for indoor use but have to be in a access/in wall box in conditioned space. Copper is big around here also, not many people use steel anymore. When I was a pup my first main job was to set up/cut metal pipe and keep pipe threader lubed. Dont miss thoes days. I dont care for CSST but alot of newer guys are pushing it. Code wise thats the only differences I see compared to my area. Like has been said vent pipe in front of coil, float switch but a neat looking job. I like how you didnt undersize return box as a lot of other companies do and get terible return noise.
Yep, as I said, only our 2nd 90+, so we'll get the hang of it.
Inspected and passed without a word on the gas piping. I use a local gas company for the piping, so no word from them on alternatives. Copper has been the standard here for 30 years, and I see it throughout attics. They are good about labeling it, though.