I only have negative experience with HCL and peroxide. That stuff is just way to corrosive imo. Ive done etching both outside and in a tool shed. I can tell you the fumes are not something to mess around with. There were some tools and blank metal sheets in the vicinity of the HCL (a couple of feet away) in the shed, and only a few hours later i noticed a lot of the tools and huge patches of sheet metal were highly corroded. Stupid mistake i guess... Well you learn the hard way
So i cannot imagine using this stuff inside your house safely.
At my school we used ferric chloride, which was actually comparable in speed but much less dangerous (though watch out for staining like mentioned before).
But if it were up to me i would look in to PCB prototyping services. Ive recently switched from home etching to elecrow (but there are lots of others as well) and cant believe the low prices they charge. It does take the fun out of etching and it takes a bit longer (like 2-3 weeks or something), but its cheaper, less dangerous en you get a higher quality board in the end. So that might be something to consider as well?