FAQ about the Global Trade HQ

I find the Global Trade HQ extremely frustrating, bordering on useless.  First you have to enter  dozens of times and/or dozens of cities to find what you're looking for.  When you finally find it, 95% of the time it is no longer actually available.  I would make two suggestions.  First, as in real life, you should be able to search for people selling what you want.  Second, and as a minimum, if an item shows up on your screen, it should be actually available.  With the number of active cities there must be, I see no reason why a hold can't be placed on an item while someone is looking at it.