CaptnBlaklava, ditto's are a bit less valued after hitmonlee fell out of fashion, they are still usefull for metagross. If It has a good nature like adament, it could go for...400k-450k, but only if you find a buyer that would be ok with buying 30 ivs. if the nature is trash, sorry It will lower it by about 100k-200k. Take in mind this is estimated with genderless in mind, not male breeding. good luck selling it. I don't recomend trying to sell it on the gtl, try selling it in person who is trying to get a comp metagross. the gtl is very misleading on true prices.
Edit: hitmonlee