Questions about taxes, duties, and licencing, are probably best asked at your local authorities due to the fact that they vary country to country.
Your biggest problem order wise is likely to be your order sizes. Factories in China generally fall into two categories:
1. large quantity, good quality, low price
2. low quantity, low quality, low price
So in most cases buyers will buy large quantities in order to get the prices that they need to be profitable with sales back home, while maintaining quality by dealing with factories who want the quantity that these buyers have to offer.
I would be very wary of any factory in China that was willing to dropshipping or piece by piece orders. There are certainly some very good factories that may accept those terms, but as they are not profitable, and generally more trouble than they are worth, you have to ask yourself what type of factory you would be dealing with!
The problem is that most factories work on low margins such that they produce for delivery. They generally don't warehouse nor maintain inventory.
So for them to send you an item or a couple of items each time they would most likely need to produce those items for delivery. As you can imagine, setting up a factory to produce one or two items is not something that most factories would want to do.
Finally, my guess is that your plan to purchase a range of items and low quantities may mean that you don't intend to actually visit suppliers BEFORE you send them any money. So there is going to be a risk there for you that you need to try to reduce. Speaking with a Chinese Helper may be in your best interests.
Having said all of this there are opportunities for what you want to do, but you will find that your process will be different than the typical buyer who contacts suppliers here at alibaba.
Feel free to contact me through the Trade Manager for more information.