Upload & Sell: On
Is that lens still available and did you take any shots? - the images may be fine. As much as I enjoy excellent/mint condition lenses for that price and how much I would (or not) use that lens - sounds like a steal.
I did not take any pictures. I brought my camera and realized I had forgotten an adapter.
I am not sure how it would perform, but it was a pretty sizeable spot of fungus. I can't imagine it wouldn't affect the pictures, but I could be wrong. A possibility is that the fungus isn't dead, either.
For the price, it may be a good deal in its current state, I was afraid of getting a $600 lens for $500 and then the fungus gets worse, and in a few months I have a $200 lens (picture quality-wise).
But, they have a 14-day no questions asked return policy. Watch for it to pop up again (the guy said it would take few days to process the return), and give it a try, and return it if you think it is affecting the picture quality.