What are the major hurdles for a Microbusiness which aims at doing e-business?

How to build trust. The biggest hurtle with e-business in the ability to build trust. Unlike traditional brick and mortar you got to try that much harder to build value and create long lasting relation that is win-win. I believe most people still want to have a face to face style of business interaction so you got to overcome that inhibition.

Good luck.

shipping calculations, cost, carriers, insurance, guaranteed delivery, and refunds of items sold.

The biggest hurdles you will have to overcome to survive more than 1 year on the net are:

A. You'll have to compete with thousands, perhaps even hundreds of thousands of similar businesses which may not only carry the same product as you do, but even at better prices.

B. Figure out what would make a customer choose your business versus the unlimited competition out there.

C. Advertising your business. With so much competition out there, how will the customers know to find you? You'll have to spend some money to make your web presence well known.

Well the worse thing that could happen is that you may not be prepared for what E business can bring to you in terms of volume, and not being able to meet your new volume in a timely manner could spell disaster in terms of E credibility
for your marketplace and name! good luck