I picked up a Canon SX50 HS with image stabilizer. So far I am pleased with the controls. I expect to have occasions where I will
use this in low light situations. Shooting cars in dim garages, etc. Would getting an accessory flash unit help with that?
I have an SX50 HS and it is a fantastic camera within certain limitations. One of those limitations is the aperture not very large, which means it is not the greatest in low light. At the wide end of the telephoto range (24mm) you will get f3.4 which isn't too bad, but as you zoom, the aperture quickly gets smaller (lets in less light). If you get a flash, get one you can use off camera. The SX50 has a pop-up flash, but those are not much use except as a fill flash when you are shooting in very bright light and need to "fill" in to soften the shadows. Your users manual lists the recommended flashes for your camera.