Re: Best .308 for under $3500?
Love this question, I'll go make the popcorn ;-)
Seriously, or semi so, browse the classifieds on here & you can find some great deals on pre-loved rifles from great builders. APA, GAP, AI, etc. That, & or talk to the smiths directly about your wants & needs in a stick. "BEST" is definitely determined on your intended use(s) for said blaster.
Also, does the $3.5k figure include glass & accessories or no? Ditto on including a trainer in .22LR configured the same as your primary stick.
Your question's pretty broad, so you might want to fill in what you plan to be the rifle's primary use(s), & what features are must haves on it.
You could even simply pick up a new or used milspec 5r & use it until you sort out what make up the particulars & specifics of your dream rifle. They shoot pretty dang well, & if it's a .308 you're after, 8+ times out of 10 they'll more than suffice. Albeit perhaps with the custom stock of your choosing.