Hi,
I use Adobe Muse and I know that if the customer hosts the website with Adobe themselves; Adobe Business Catalyst, at just under £5 per month, then they can automatically log into their site as an admin user and edit photos that are already there and edit text. Muse is Adobe's stab at CMS sites.
If you are using dreamweaver then if you are a Creative Cloud Member, do you have access to Adobe Muse too? I know I have access to everything Adobe have created, as a paying member. It is incredibly easy to learn.
If it was the autoshop I would consider subscribing to www.wazala.com. I could have a shop, which I can add new photos, descriptions and prices etc. The site generates the code that goes on your web page. This would mean that rather than your customer having to edit the site itself, they just go to www.wazala.com and do it there. It's very user friendly. It can also link to PayPal etc and works as a fully functioning shop. The good thing about Wazala is that you can also add it onto your Facebook too...so if they also have a Facebook, their shop will appear there too! Check it out, it's worth knowing about. It would also be a good option for any small shop that you might create a website for.
Hope this helps.
Sebastian