There are homemade soda carbonators for sale on ebay that can be a pretty good deal. Something like this is what I have: https://www.ebay.com/itm/Kegman-Seltzer

There are homemade soda carbonators for sale on ebay that can be a pretty good deal. Something like this is what I have: https://www.ebay.com/itm/Kegman-Seltzer-Making-Bottling-Kit-with-CO2-tank/254010998330 https://www.ebay.com/itm/Kegman-Seltzer-Making-Bottling-Kit-... The price is basically the same as sourcing the parts (regulator, tubing, tank, etc) yourself, it comes pre-assembled, that size CO2 tank will last a while (around a year for us with multiple people in the hot south), costs $15 to refill, and you can dial up/down the pressure to change the bubbliness of your soda. It's also useful for seating tubeless tires if you ride mountain bikes. :)