You can pay $15-25 for a DNA test. Of course, you would already have to purchase the birds, collect the samples and mail them in and then wait for the results to come back. Other than that, you're at the mercy of time. Most of mine I can't tell gender on until they're 3-6 months old, though I do...
And for future reference, its perfectly acceptable to put all of your questions into one single post rather than a bunch of separate ones. It's keeps the forum from getting cluttered up. I'd suggest you head to the Breeding, Showing and Genetics section of doing a forum search for the Silkie...
Lots of people keep lots of different breeds as house pets. Silkies are a good option because they're generally docile and they can't fly. However, at the end of the day, they're still chickens. I keep mine in a coop just like any "normal" breed. They go out in the rain, snow, whatever and they...