Not worth it.
Saas rule. For really small denyuzhku you maximum functionality with all the selling items such as upsell, crossell, shares, additional sales, etc. out of the box, adaptiv, tech support, a bunch of design templates and finished templates to suit your needs.
But to start and test your niche you can do for free for a trial period.
I love insales, if you want to additionally throw off a large list of saas systems for THEM in the comments.