Genuine question - why are UVs always a huge issue? Isn't it trivial to generate a UV from the actual 3D model? Or do you mean that they just don't give you an image that actually fits the model?
In the case of an artist working from scratch the skill is generating UVs that allow the artist to easily paint the texture and provide an even area for each part of the model. Otherwise some areas will be stretched and blurry.