Honestly, aside from the price I would really focus on your presentation. Most of these look like viewport screenshots, take the time time render these in a good lighting environment with different subdivision levels to show how you can improve the resolution, displacements etc. Give more information as well as you only provide 2 sentences.
For example, what is the texture resolution, polygon count, is it able to be realtime, offline rendering? Can it be transfered to other render engines, other software packages? What is the unit size? Are they unwrapped, what is the texel density? You dont list this information, imagine yourself as the buyer, they want to know as much as possible before buying the item.
A side note about low poly work, if its low poly then people expect high resolution texture work. Remember the people you are selling to are 3d artists, if they could make this quickly then they wouldnt buy it. Its a trade of time/quality, if it takes them longer than a day to make then they will happily pay half a days rate for example.
For example.
