German larp Epic Empires seems to have had a 90.95 Euro kit challenge and released the resulting tutorials:
Its in German, but apparently reasonably easy to follow with Google translate.
The costumes are interesting, but so is the international comparison. A few years back UK larp Odyssey had a £30 kit challenge, which focused on minimising both cost and skill required for entry. The German one is more expensive, but also has much higher skill requirements: entries involve making your own shoes, doing embroidery, or hand-weaving your own trim. It’s about accepting a minimum budget and asking how great can you look for that amount, rather than seeking to minimise costs completely.