Is it possible to do a job with someone who has already done it

To replay heists that you have already completed, you need to cancel your current heist. Then call Lester, select "Replay A Heist," and choose which one you want.

You can use this to request specific heists. You can call anyone who offers you jobs to request that they send you a job, but they'll send you a random one from the list of jobs you have completed for them. You also need to wait a bit in between requesting jobs from the same individual if you are looking for a specific mission, roughly a minute or two between requests.

Once you have completed each heist, you are free to replay them whenever you want.

Do note: Starting one of the previous heists will start a heist "save" like usual, causing you to not be able to host other ones until you complete/quit your current one.