its one thing to be able to lift something and move it around carefully and not damage it or the surroundings but another to move something that is quite a bit heavier and not be sure if you will damage it, the surroundings (ie your car ) or damage you.
would suggest you take someone with you, or when you are there look around for someone to give you a hand.
in the summer i leave the sib inflated and put in on the roof of the landy, when at the beach i always look around for someone to help lift it off the roof, it is not heavy but want to lift it vertically off the car so not to scratch the car. i always look for someone tall and reasonably strong rather than a shorty who looks like he has a bad back.
noone has declined yet!! in fact choose someone who is there with their bird and they pump up 3 chest sizes, the sib looks heavier than it actually is so they usually look quite chuffed with themselves...
have a yam 15 that weighs around 37 kg which is fine for moving around on your own but you dont want to carry it far, 50kg is ok for short distance, 60kg plus is getting a real handful