Both my husband and I have been active donors of plasma. I did stop after about a year because my iron readings weren't where they needed to be. My husband still donates twice a week and has been for 2 years now. They will do a basic high school physical and ask lots of questions before you are qualified to donate. They will assess your veins to see if they are useable.
If anyone is caught lying in the questionnaire, I believe you can be banded for life. They seem to run some kind of a bonus program for new folks along with seasons donors. They want you coming back, and that's not a bad thing.
The funds my husband has received has helped out in many ways and provides a bit of mad money as well. It's a win-win program IMO.
I'm not going lie...the needle is huge compared to a shot you get in the arm. In fact, I don't feel those anymore. LOL
Write all YOUR questions down before going in and make sure you are comfortable with the process. Good luck.