Jeez, what did they use, a brillo pad?
In reality, I doubt it'd make a huge difference. I recall there was a test where someone hammered the front element of a lens and noticed only a drop in contrast, or something like that. As such, I suspect that these marks might not have much effect. The only exception would be when shooting into strong light; you're likely to see increased flare as a result of these marks.
How cheap is cheap, btw?
Also, If it's too good a deal to pass up, the good thing about LF lenses is that in time, you can keep an eye on the second hand market and look for people who are selling the front and rear lens groups separately. Just replace the front group as and when you can get it.