Wanting too get a motion decoy or two,, what woudl you get and why,?
This is for a borrow pit water, amateur hunters but we do kill some ducks

We have Higdon Pulsators. Great action on calm days, the splash of water attracts birds, and it really takes a good charge. Helped us limit on a dead calm day recently.

Jerk string

Jerk string and maybe a remote control spin wing decoy.

Jerk string with 2-3 decoys works well and it’s cheap to make. Look up on Utube

Higdon pulsator or a jerk rig

Jerk cord works good as long as you don't have a dog. They always get tangled up in the cord it seems.

On calm days we'll run 4-6 wonder ducks and a few spinners if the sun is shining. Stale birds flare off both, so be prepared to pull them.

Jerk

Jerk

I typically do not run a jerk cord as the lab usually tows the line when retrieving.
The limit is 10 ducks up here in Alaska so lots of back and forth for the dog.

I do like the random on and off of the mojo flock of a flickers.
To the left of the lab picking up the duck in this video:

They have worked well for the past 3 seasons for me.

On your jerk lines place rubber lined sinker every couple of feet between the blind and the decoy, lead core trolling liine would work also, tie in a piece every few feet if the sinkers don't move fast enough or return. They line will stay on the bottom and out of your dogs legs. I used to run long lines off the beach in tidal areas. I'd set the decoys at low tide and as the tide moved in I didn't have to wade out to reset the decoys just pull on the strings. Weights on the lines and 2 ft doppers kept the dog free of entanglement. Some places we were moving a 100 yards or so. It should work for your jerk lines