Just to share, it's often not worth the trouble and risk buying a fungus-ed lens. If you were offered at second hand shops or BNS, think carefully.
Especially if the fungus had been there for a long time; ie; especially those old lenses, because Fungus feed on lens coatings, the longer it is there, the more serious the damage. And the damage is irreversible and permanent, in a financially sound sense.
How much to pay for a fungus-ed lens? Answer is don't buy it.
Assuming common pre owned price for a certain lens is $600, lens cleaning cost $120 to $200 (I know there are cheaper options but it is not always available, trustable or time practical, you don't want to wait a year for lense cleaning... Lets just treat as $200 to factor in the trouble, time and transport fees to get it fixed. So that brings down the price to $400, but remember this is a lens that suffered fungus, very likely its coating was damaged, there's chance of recurring outbreak with the right conditions, there's chance of it infecting other gear.
So I personally won't pay more than 50% of that $400 so max is $200, for such a small difference of few hundred dollars, I rather look for a healthy lens and not worry about using good money to buy frustration and anguish.
Especially if the fungus had been there for a long time; ie; especially those old lenses, because Fungus feed on lens coatings, the longer it is there, the more serious the damage. And the damage is irreversible and permanent, in a financially sound sense.
How much to pay for a fungus-ed lens? Answer is don't buy it.
Assuming common pre owned price for a certain lens is $600, lens cleaning cost $120 to $200 (I know there are cheaper options but it is not always available, trustable or time practical, you don't want to wait a year for lense cleaning... Lets just treat as $200 to factor in the trouble, time and transport fees to get it fixed. So that brings down the price to $400, but remember this is a lens that suffered fungus, very likely its coating was damaged, there's chance of recurring outbreak with the right conditions, there's chance of it infecting other gear.
So I personally won't pay more than 50% of that $400 so max is $200, for such a small difference of few hundred dollars, I rather look for a healthy lens and not worry about using good money to buy frustration and anguish.