This mod will increase ammo you can buy but it will also be more expesive.
To see the prices and ammo you have to download and open this shopping.dat file, then press Ctrl+F and type: # weapontype,
and click the 'Search' button.
You will now see the weapons. You can adjust the prices and amount of ammo as you like.
Note: I recommend to install this mod after buying Verdant Meadows since you probably cannot afford a lot of ammo before that.
How to install this mod:
Download this mod, copy and paste this in the 'Data' folder of the San Andreas folder. Always make a backup first.
I am not responsible for any trouble this mod may cause.