If you and some friends are going somewhere and you say, "Hey, instead of driving, how about I get a plane, we evenly split the costs and we'll get there in a third of the time." That's legal. When you say "to build time" it starts to get a bit iffy. The FAA has ruled that flight time has value to a pilot trying to upgrade their certificate. So you were "paid" in hours toward your next checkride. If you've got a 121 job now, I'd say the stale complaint rule kicks in and you're safe.

Thanks for the clarifying Twin Wasp. I never looked at the fact with "payment in time" would be a factor there. Thanks again for the input on that.

Consider calling AOPA legal service. I think they get this question a lot. There are several things to consider but I do not know what they are. Please when you do post here on this forum what you learn, as I would also like to know the answer. But I believe it was OK to advertise to share the ride.

Jeff001