New member, 06 4.0, common issues?

[Incision]

I recently purchased an 06 v6 with 80k miles. It shows signs of sitting for some time, today I had to replace the battery, coolant tank and hoses, and for now disconnect one of my door speakers because it’s popping even when the cars off. I suspect it’s draining battery power. Tomorrow’s job is brakes and calipers. What other common issues do these usually have? I plan on fixing it up, and learn to supe it up a bit for drifting. The starter, ac compressor, and thermostat housing all look relatively new. Not pissing oil but I’m pretty confident these are all original seals so I’ll need to get on that next.