Additional thoughts and ideas:

Years ago I bought a carbonation set (like Soda Stream) so I don't remember the price for the plastic housing. I buy 1-2 CO2 cartridges per year (€ 10 per cartridge) to make my own sparkling drinks.

Stop eating tortillas. They are expensive to buy in the store, and quite fat. Buy more beans, rice, and vegetable filling and eat more of that instead. Save money, better nutrition, less fat. No downside. Note this applies to bread in general.