Tactful way to say "No thank you" due to safety.
Someone I know well encountered an interesting situation recently. She was invited on a ride with a couple of new horse acquaintances, one of whom was her BO. The BO offered to haul a couple of horses.
When everyone arrived, there were a number of safety issues with the BO's trailer.
Luckily, one of the other riders saw this as well and quickly swooped in and "accidentally" loaded the horse in question onto a different trailer so no harm done.
But the situation is liable to pop up again very soon. If you were (kindly and generously) being offered a ride but felt that the rig was unsafe, what would you say to someone who also happened to be your BO and had no qualms putting her own horse in said trailer?
I'm not talking about safety stuff like "Ohhh! She doesn't use quick release trailer ties!" or "Ohhh! She doesn't have padded butt bars!" I'm talking rotten floor, bad tires, electrical not working, etc. Something more major.