Can you clean dust from the inside of the elements?

I'm looking at a nikon nikkor 80-200 f/2.8 lens on ebay and it has some dust on the inside of the elements can you clean that or will it not make any difference to the pictures

Anything in the light path will have a theoretical effect on the image but whether you could actually see a difference or not is a different matter. Cleaning is possible but it needs a skilled repairer and they deservedly get paid a lot.

Every lens that I have owned has visible dust on the interior elements. It does not affect picture quality in any noticeable way unless the lens has been abused and is loaded up with dust and moisture. The two in combination lead to fungal growth which can affect picture quality. You can't clean it yourself unless you are a trained lens technician with the specialized tools for disassembling the lens.

However, if you are buying a used lens, I do not recommend it unless you can actually examine it. I'm a bit paranoid about it, but I assume that buying a used lens off e-Bay or Craigslist is a gamble. There's a possibility that it's either broken or stolen. Mind you, I do know of people who have gotten good stuff in that way.

A small amount of dust on or in your lens will make very little difference 90% of the time you are shooting. The big exception is when you are pointing directly at a light source. In that case, the dust can "light up" causing increased flare and other problems.

It can be cleaned, but it is nearly impossible to do yourself. However, you can send the lens back to Nikor and they can clean the inside of it for around $150.

If the lens it a good deal, it might be worth it to buy it and try it out to see if the dust is even noticeable, keeping in mind that you might be paying for a repair.

Also, I tend to like buying things from people that are honest about the defects that an item has.