Build a backyard zip line

Hi, I don;t know if this is the right forum for this topic, but I am looking for advice on building a backyard zip line as follows"

-106' between two trees (pitch pine) over flat ground. So I would install starting point of line higher up on one tree than end point of opposing tree.
-I plan on tying around the trees on both ends as opposed to a bolt through.
-I would like both children and adults to be able to use, so need something rated for 250+pounds.
-Looking at some of the kits for sale at various websites.

So here is my wish list:
I would like a kit that has everything, but the cable lengths offered are 75', 100', 150'. Distance between tress is 106'. By everything I mean, extras like harness, seat, brake block, etc.

I would like to use a gravity stop type braking with a stop block for safety. Although one kit (Alien Flier I believe) offers a trolley with a trigger style brake built in, which is appealing.

I would like a detachable trolley with closed top, so if someone happens to grab the top of the trolley while in motion they won't injure their hands.

So I'm not sure if I should piece a kit together separately, or buy a kit and cable separate, or if their is a complete kit that has everything I need. Budget is max $400, ideally.

Also, are the trees I want to use ok for this? Pitch Pines tend to sway a lot in the wind, so not sure if they are even the proper tree to begin with...

Thanks for any suggestions, and if there is a better forum out there for this please let me know!

Before you buy gear you need to have an understanding of the amplified loads on the ends of a zip line. In some setups the static load can be multiplied by factors of ten twenty thirty! The gear might not break but what about the anchor points

Do a search here for zip line or speedline loads. You'll regret not doing your engineering if the trees break

Check out www.ziplinestop.com they have a great blog that is really informative.