So it's kind of meaningless to make ammo or buy ammo. Particularly if you've added another mod, Restrict Crafting to Apartments Only, which makes it more difficult to produce extra ammunition without having to travel back to your apartment.
It seems worthless to go to a weapon merchant every five minutes to replenish your ammo; it scarcely costs anything and you will quickly burn through it again.

To make your game a little lot easier and more efficient, Refill Ammo from Vehicle Trunk is the right mod to use. It is a mod that lets you refill most of your ammo by opening your own vehicle trunk or hood.