Hello John Dragun,
As you mentioned above you've only one seller, you can disable the Marketplace from Sellacious Administrator > Settings > Global configuration > General. After that Sold will be disabled for the products, cart.
And to change the color price, do you want to change the color price only or of your whole site. To change the color of your whole site from blue to Black, go to Joomla administrator > Extensions > Templates. Select the style you want, and in preset select the color black.
And to change the color only of price, please go to
../templates/squick/css/sella-preset.css
and add
.mainprice .product-price{
color: #000000;
}
at last of the file. The color of price on product details page will change.
I hope this will help.
Thank You
-Team Sellacious