2005 5spd manual, 205k miles, starts and runs, moderate fixable dents in bumpers, $2400

My car for example :
My first car is a 2012 Scion tC, I wanted this car just to specifically mod it & make it a project car but also not ruin it in the making. I really do need help with what I should & shouldnt do, but I do have an idea of stuff I want to do. So please someone de-influence OR influence me !!! Feel free to give harsh advice, whatever.

- TRD exhaust or borla axe-back exhaust
- 2015-2021 black STI spoiler
- Lowering springs and lowering it about 1-1.5 inches
- Spec D headlights & taillights
- Black emblem in the back & debadge the front.
- Wrap the hood, roof, and trunk black

The car is not bone stock. It has a subwoofer, cold air intake, and oem rims. Will it be reliable?

Currently trying to determine if I should buy a new/used car. My tc is 15 years old - 2011 - and all things considered, doing quite well. It currently needs about $2000 worth of work done to it, and has 180,000 km / 112,000 miles on it. We have some upcoming job instability but not sure if it makes more sense to get a newer car to avoid upcoming repairs that will inevitably be more expensive, or keep the tC for a future of unknown repair requirements.

How did you decide it was time?