Other than the design of your site, there is little need of a pro. There are many free and low cost online stores available that need virtually no actual website experience to operate an online shopping cart.
It will help to have a few html goodies in your head, but they are simple and easy to remember. <b> and </b> before and after a phrase you want to make bold. Then there is i for italic, u for underline and <font size and color> for changing sizes and colors. See, now you're an expert.
And some carts, such as CubeCart come with built in html editors, so you just highlight what you want to change and click the icon, just like MS Word.
As I've said other places, the main thing with a cart is setting it up the first time, and that is basically answering questions. What is you address, what is your tax rate, what is your currency, etc. None of this requires knowing anything axcept the answers, which you type in or choose from a list.
I've started many a neophyte (newbie) off with a shopping cart that they have had ready to go within a day or two. Virtually everything is done for you. There is no "building a website", it's already done.
The only place you may want a "pro" is in the look of the site. The out of the box choices are pretty limited, but there are any number of free or paid for templates (or skins) available and there are some folks who will design one from scratch, just for you.
Many people do want a distinct look for their shopping carts, others don't really care. My attituce has always been - when is the last time you left a site because you recognized they were using a default site template? People come to your site because you managed to get them there, they come to buy, not judge your template. I'm not saying it is not a good idea to have something unique, but it is not the be all end all of online stores. Many large companies sell from basic free shopping cart sites.
So, be getting your products together. Gather your images, you'll need them. Spend some time on the net at the various sites devoted to learning web ways. But in the back of your mind keep the thought that "I've got it handled." because you really can have a cart online with little or no web knowledge. What little you need to know you'll pick up in short order.
As an example, here is a sample CubeCart store I use for people like you to check out. Click the link and check it out. The user name is admin and the password is (get ready for this) password.
http://smallbusinesshoster.com/cubec...dmin/index.php
You'll see it's not so complicated at all.