if the largest you want to print is 8 by 10, get 11 by 14 trays so the prints can slosh back and forth a bit and will be easier to get out.
Get print tongs so you don't have to be putting your fingers in the chemistry.
Don't worry about covering the mirror -- reflected dark does not hurt prints, and there will be very little light from the enlarger flying around to worry about.
I have two safelights -- one between the enlarger and the paper safe so i can see what I'm doing there, and one over the trays.
Shop around for safelights -- the paper you use will tell you what is the best color, but the danger is not large if your particular safelight is not precisely the right one. Most safelights now are more orange than bright red. Years ago I used a small candle four feet away for a safelight and it worked fine.
Now I have one that uses LEDs and can be switched for three different types of paper... but my other over the trays is a standard very old filtered light with a low-wattage bulb in it. Both are orangish. The kind with filters and regular bulbs will be easier in the long-run because, when the bulb burns out, it is cheaper to replace.