CSW! It is interesting you say you don't want to pursue MMA but you are talking about mixing your martial arts. :) Maybe you mean you don't want to fight in a cage for money?
Note that the gold reflector will shift the colour temperature of everything it hits, so if you're photographing a model wearing white, and that white has to look white in the final picture, you're just going to have to put things back the way they were in post anyway
A mirror might look silver because it's usually depicted that way in books or movies. However, it's actually the color of whatever is reflected onto it. A perfect mirror has specular reflection, meaning it reflects all light in a single direction equal to what it receives. Specular reflection creates an image of whatever object is in front of it. But most mirrors we use aren't perfect.