Hi, my question is simple: can I buy and use a photo for a PS contest from istockphoto or places like that?
Thank you

yes you can enblanco as long as it is an image, not manipulated or art I believe.
Then show proof of purchase and link.
If I am wrong someone will correct me. When in doubt ask a mod is a safe bet.

Yes cabldawg71 is right, post the bill of purchase in your SBS. You are allowed to black out your personal stuff on it like your name and accountnumber.

Hi, thank you for your answers.
The proof of payment in SBS or to a moderator via message?
TY

sbs but be sure to black your name out to stay Anonymous.

Ok, another question: I'm a graphic designer so somethimes I buy photos from stocks for my works and projects, in this sources I can post the proof of payment, no problem. But sometimes I choose the images and clients want to buy those images for themselves and then they send to me to work in their projects, I have all the rights of use of this sources but I have no proof of payment... so I suppose I can't use those pictures, am I right?
Thank you for your patience.

Seems it would not be a problem to use said images for client projects, but those images would not be allowed for use in pxl contest.