I’m using an APC 3000 that I got with no batteries.
Your choice should depend on load and needed run time. Mine is around 1200 watts 😮💨, so I need higher VA rating.
I also took out the stock 12 amp hour batteries and I use much larger ones. Don’t consider that unless your unit is managed, actively cooled like having fans, and can do thermal shutdown.
People have tried this on the cheaper home use products and burnt their house down because the cheap products are designed for the battery to die before the unit gets so hot it fails and burns. Then some kid extends the run time way past that with car batteries. 🔥