Go to settings -> Diagnostic and deactivate Automatically calculate reasonable price

Now install any mod that adds some kind of Product

Locate the folder in which your steam install your games and go in
steamapps -> common -> VPet -> mod -> 0000_core -> food and open the file that contains the item you would like to modify

(you can use every app that read text files to open this files, in my case I'm gonna use Notepad)


(in this case I'm gonna open moredrink.lps)

And now change the experience that the item you want to change give, like in the image


After doing this, save and close the file.

You can now restart VPet simulator

Now feed the VPet with the item you choose, and the level are gonna go up



PLEASE NOTE: all the stats are gonna drastically deploy and need some time to restore