The McLaren that I investigated had some rather nutty costs.
First, I intend to track my sports cars, and I do, a lot. The McLaren engine costs about $80,000 for the crate motor, if you ever need a new one, but their warranty covers track usage, so I decided I wanted to keep the warranty. It broke down like this:
warranty: $11k/2 years. You can extend this warranty for a while, IIRC, it was possible for 8 more years on the 600LT
inspections: $600 pre-trackday and $600 post-trackday inspection required + whatever maintenance items are needed.
You can do pre-track inspection within ~week of your track day, and post-track needs to be done within 3 days.
So, there's a strict inspection/maintenance regimen at the dealer to keep your warranty. I assumed I'd be doing ~10 track days per years in this car, so I'd need to budget $12,000 just for the inspections.
CCB brake rotors are about $6k each and last about 10 track days. Thats kinda bonkers, but aftermarket alternatives exist, like SurfaceTransforms, that are a lot cheaper. If you go with iron rotors, you lose warranty on the suspension.
Once I did all the numbers, I decided it wasn't worth the constant trips to the dealer and the hassle.
I can afford a 2GR-FE engine without worrying about it.