Get Meowth in your fighting roster. During battle, transform into Gigantamax Meowth. Then pop the G-Max Gold Rush move. This has a good chance of pocketing you up to 100 times the cash of Meowth’s level! Equip the Luck Incense (from Hulbury market) or Amulet Coin (found near the cave entrance on Motostoke Outskirts) for even more money.
Ditto is a super-handy Pokémon to have on hand for breeding the best Poké-pals. And the best Ditto is one with Max IV stats. You can find a statted-out Ditto in a random encounter at Lake of Outrage after you beat the game. Keep hunting until you get the Max IV Ditto drop you desire!
Want cheaper prices at the vending machines in the Isle of Armor DLC? Once you get Kubfu, head to the Master Dojo and chat with Honey to get cheaper prices at the vending machines. You can also upgrade the machines by giving Honey Watts. Trade 30,000 Watts for a Fresh Water Vending Machine and 200,000 Watts for a Protein and Iron Vending Machine.