Is it okay for graphic makers to sell an individual picture on more than one sim? For example, you make a layout image and sell it to someone here on HP and than go to Horseland.com and sell the same picture to a player on there. I don't see it too often, but sometimes I'll see a manipulation on here and then go to HL and see the same one. I haven't done this (but sometimes I'll make a manipulation for a club competition where it's just for fun and won't be used again and then I'll go to another site and sell it).

I think players usually pay a lot of money for their layouts and horse/dog pictures and giving the manipulation exclusively to whoever bought it is kind of a given. I'm also unaware if there is any official rule against this on HP or in general. I'm just wondering everyone's opinion on this and I guess it could be a pretty clear answer but I'm still curious as to what everyone thinks.

Hmm, I've never even thought about this (probz since I don't play any other games besides HP).. but I always assume when I buy graphics that I'm the exclusive "owner"/user of the graphic. To sell it to multiple people on multiple games kinda feels like double-dealing to me. I don't think there are any rules currently in place though.

I think it's different if, like in the example you gave, you made it for one game but it wasn't used, or it was used for something like a one-month club layout. But if you sell it, I think that should be the end of it. Just my opinion ofc!

I had this happen to me - she sold a layout that apparently had been a commissoon for someone on HL, and the person who bought it on HL got quite upset and told me not to use it (though I had paid good HPD for it....), so I messahed the seller about it and they flatly refused a refund and told me to go ahead and use it anyway, even though the other person had paid RLD for it :/ I double check images are exclusive before I buy now

There aren't any specific rules against it, but I think it's pretty shady, ESPECIALLY when someone has paid real money though a comission on DA or something...

Well I think if you're buying something for real money it had better be solely for the buyer and for the artist's protfolio. 

I think it is rude to allow anyone other than the original purchaser to use commissioned art (whether for real-life or SIM money).  That's the problem with digital art - it is so easy to just sell another copy.  With traditional media, you can't just copy & paste like this.  If you sell a painting to somebody, they own it, pure and simple.  That is how digital art needs to be treated.

The only exception I make is with non-commission art, and even then I will notify people if I intend to make it available elsewhere for sale.  This is more common with tag bases, but sometimes happens with paintings or manipulations.  I know some artists on DA will allow their art to be used for RPG characters, and there is no limit to how many they allow to use it - as long as everybody else is okay with it.