Like a Dragon: Infinite Wealth

Once you've come to Dondoko Island, you'll learn the ins and outs of crafting via the DIY bench, which is found outside Kasuga's house. Crafting items requires blueprints, which can be found, purchased, and acquired by myriad other means, both on and off Dondoko Island. To craft an item, interact with the DIY bench, then make whatever you want for your island using any resources you've accumulated. Resources are everywhere, but the most abundant are to be found in the piles of trash you bash to bits with your baseball bat and at the collection point. Hoard as much fabric, plastic, metal, glass, semiconductors, wood, and rock as you can, and you'll be able to make almost anything you like. 100 furniture things specifically, in this case. Also, the more you craft, the more your building talent level goes up, unlocking more and more blueprints.