I just went through rethinking this for my business. When working in the suburbs, you can always run out to a well stocked truck.
But, in the city, when "running out to the truck" isn't so simple, how do you put together a kit of parts that will meet your needs a large percentage of the time without having to carry half your truck into the apartment?
As far as patch cables go, I haven't yet found anything I like better than rugged totes (sometimes marketed as soft tool bags:
[Link: homedepot.com]What they lack in sorting, they make up for in lightness, ruggedness and portability.