We are currently working on improving an online e-commerce website, and recently we bumped into the issue of adding an explanatory legend that had not previously been requested.
There's a product listing and each product comes with individual characteristics like shown in the picture:
We already use tooltips to show some aditional information about the product, so that's not the solution. We also know it is not a good practice to link explanations with asterisks.
What needs to be done is to add the legend 'Tax included', but it doesn't fit anywhere without affecting the current layout.
I can't really put it next to the price (although it would seem like I can) because this site also sells for SouthAmerican countries and their prices go up to 7 digits, which gives me almost no room for it (appears too tightened).