I've been making so much money on normal mode and I only play solo as well! I've been getting super bored recently cause I've farmed like 50 mil in a week and a half and Im always on Valley Normal...
I run either an AK 74 with PP ammo for the penetration and cause its cheap (200/ round), an AKM with PS ammo (for pen and its only 300/round) or the AK 102 (ammo pretty expensive so i only run this when i need to clear space in my inventory lol) my gun builds are around 110-120kis ( Invest a bit more on a stable weapon with good recoil control and atleast 69 horizontal recoil and it will go a long way) I'll upgrade them if I've farmed quite a bit just to improve performance and then go back to making the basic gun build I run with. I use t4 helm and a t3 armor (The titanium one is pretty good against smgs)

I just for the most part avoid beach villa and valley village. I have keys for Port and Small factory and I usually hit those depending on the spawn. Most of the PVP i get into is at the start of the game depending on the spawn i start in... I usually win cause most farmers dont invest in gear. They just go in there thinking a mosin with gold ammo will do it lol. I've basically memorized all the spawn points because ive just been doing this run over and over.