The divers brave jellyfish-infested water to test this prototype. I was afraid someone would got stung in the face. Also, did some jellyfishes got shredded at 0:11?
According to Ukrainian media, the Marichka is a self-developed system made by volunteer engineers (so called AMMO UKRAINE) with donations. The media platforms claim that the estimated cost of the UUV is about UAH 16 million, which is equivalent to $433,000.
If you can see the propeller, you can figure out the sound profile it would make and listen for that. That’s why they always hide propellers from views in pictures of modern submarines.