Do it by myself with Magento or use something like Weebly, etc?

I just started working at a company that specializes in Magento. The biggest thing I've learned is that Magento is not intuitive. If you are just building a simple online store, the hassle of learning and configuring Magento will outweigh the benefits of its power and customization. In other words, it might be better to stick with something simpler.

Unless you're building a huge online store with lots of different products, or multiple stores, with products in common (multistore scenario) Magento is really not what you want. It's huge, cumbersome, slow and hard to set up and deal with if you're using the community edition. Magento's hosted option, Magento GO is probably better for this case, but lack any real customisation outside of some rudimentary plugins. Otherwise to set up a Magento store you'll need at least a VPS and some real speed optimisation.

Wix will lack the scope you need to improve your store, you should always plan for growth. For instance; down the line you want to add extra features but Wix won't provide them, or charges a huge amount for them - you have to start from scratch. Your order data and product base may be lost.

Popular eCommerce systems, ones you can host yourself, for small to medium online stores are:

Wordpress's WooCommerce by Woothemes

Prestashop

Shopify

There are tutorials here on Treehouse for setting up a Wordpress website and using it as a CMS, and a tutorial here for How to build an ecommerce site using WooCommerce

Woww thanks Sam and Lauren for your quick answers! I really appreciate it. I will take a look at the options Lauren wrote, it seems that they could be what I'm looking for.