Most of the cost of a UGC video is in the planning and the creator's time, not the extra few minutes it takes to shoot a second version of a shot or export a second cut. Which means the easiest way to get more value from the same budget isn't shooting more videos. It's using each one more than once.
That only works if the plan for multiple uses exists before the shoot, not after someone on the team asks "can we use this for email too" during editing.
Decide the uses upfront
Organic post, paid ad, email content, a testimonial on the product page, a still frame for a carousel. Each of these has different requirements, and it's much easier to shoot with all of them in mind than to go back and ask a creator for one more take after the fact. This doesn't mean shooting five completely different videos. It usually means a couple of small additions to the same shoot: a beauty shot with no captions burned in, a second take of the hook without the platform-specific opener, a few extra seconds of B-roll.
Build in the variations that are cheap to get
Two or three hook options from the same creator, in the same session, cost very little extra and give you real testing material. A version with captions burned in and one without covers both organic posting and a paid setup where the platform adds its own captions. These are small asks during a shoot and expensive to go back for later.
Know what doesn't repurpose well
A video built entirely around a platform-specific trend or sound doesn't hold up as well six months later on a different channel. A hook written for a cold paid audience can feel oddly aggressive dropped into an email to existing customers. Repurposing works best when the core of the video, the product point, the creator's actual opinion, travels well, even if the wrapper around it needs to change per channel.
The actual payoff
None of this changes what a single shoot costs very much. What it changes is how much usable content comes out the other side. A brief written with three or four downstream uses in mind, and a shoot that spends an extra ten minutes covering them, routinely produces two or three times the usable assets of a brief written for one channel and used for one channel.