The dictionary (not quite sure WHICH dictionary...) states Guars as,"the guar is the dominant domesticated herd animal of Morrowind, useful as a pack animal and for its meat and hides". The first two are indeed true. The second two are only for a sick guar-murdering pyscho.
Guars would be classified in some sort of Textbook as "very cute bipedal lizards who are quite like a mixture of a cow and a horse". They gained such an enormous amount of fans due to their faces. Their cute lil' faces. I just wanna pet them. Hit them with a stick and they'll probably just cock their head and then carry on eating grass.
Within the PackGuar mod, an inexperienced guar costs 1,000 septims, a weak but experienced guar will set you back 3,000 septims and a strong fully experienced guar will deprive you of 10,000 septims. It's well worth downloading, and their very cute when they follow you, especially when they get stuck, it's so funny, watching them try to move...