Depends on how hard you are prepared to cut the cost. If you're designing for cheap LEDs, then it might be up to 80% of the cost. But it's worth it because eve

Depends on how hard you are prepared to cut the cost. If you're designing for cheap LEDs, then it might be up to 80% of the cost. But it's worth it because even cheap trash LEDs will last tens of years. If you go for good nice LEDs then maybe 50%. This would be indestructible, but it will cost you.