Ecommerce Advice URGENT

1. Getting a decent design made, and choosing a decent cart YOU can work with. I can work with PrestaShop because it's easy, I have someone else operate my Magento cart.
2. I would have paid more upfront for a good designer with a guarantee. Do you want a professional painting company to design the outside of a brick and mortar store, or do you want a couple people off the street that you thinking might be able to do a good job? You'll want a professional.
3. As much as I hate to say this, avoid overseas freelancers from oDesk and Freelance. Even people with a bunch of references may not know what to do. I only speak out of experience, but it's obvious who I've had better success with.
4. Getting traffic to eCommerce stores is actually really fun. Articles, Reviews, Building back links. I advertise my products on eBay, and I make more than I would selling on eBay.
5. I stuck with two. Magento and PrestaShop. Magento is for my large eCommerce websites, and Presta is for my smaller niche stores.
6. A decent design that looks professional, good quality products, and a Live Chat to answer questions quickly.
7. None.
8. I invested $4,000 in my first large eCommerce website which involved hiring people to write short descriptions, do SEO for each item, and export my products from eBay and Amazon onto my site. I made it back within two months. If I had instantly started linking my eBay pages to my website (sending eBay traffic to my eCommerce store) then it would have taken less time.

Selling products is fun. Owning an eCommerce website, you have the ability to say "I own ______.com" and it's a good feeling. Shopping is fun, getting repeat customers is fun, the Christmas season is fun. I almost hate logging into eBay and Amazon, and I probably value eBay buyers less than I should compared to my own actual customers.

Oh...and... Don't use PayPal. Get a real merchant, accept PayPal payments, and probably save money too.

@ FaJeeb Thank you very much for a detailed answer. I have looked into a magento solution. Did you have any problems exporting CSV file? I have heard there are some problems it crashes?

How many products do your store carry. When you mean large ecommerce ? Just curious. So you created new description for each of your items? Why not to use manufacturer description ?

For Magento would you recommend Authorize.net merchant?
How did you start making money within 2 months? Is the niche not competitive. I know you do not want to reveal your niche but if you can give me some clues PM for examples please.

Thanks for the info.. I have been researching for my first ecommerce site. But i just would not know what do you mean by large site - how many items are there?