You may find safety in numbers in an online mall if you're just beginning an online business. Visitors to the mall mean traffic to your site even before you get listed with search engines. Specialty malls in particular may help you promote niche market products. The most attractive aspect of online malls for beginning retailers is the relatively low start-up cost. The owner typically supplies a Web store building tool that includes a shopping cart system.
Some malls also handle credit card processing for their member merchants.
These services let you avoid the cost associated with Web design, merchant accounts, Web hosts, etc. Commissions and other fees may cost more than you anticipate. Often, that will still be less than what you'd pay as an independent retailer, but be sure you know what you're signing up for. Pay close attention to the mall's store building tool. Some tools limit you to a specific layout and color scheme, which results in all the stores in the mall looking exactly alike.