If the damage is just on the roof itself (in between the weather strips) then it would be fairly easy to just paint the roof because it's a seperate panel to the rest seperated by the weather strips.

Then a good machine polish on the rest of the car would see the colour be more in line. Especially as the roof is at a completely different angle to the rest of the car and you just won't see the marginal difference in colour.
It's also only a single days work for a decent painter. Anyone that tells you otherwise is just ripping you off.

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605whp
Quarter Mile in 10.9 seconds @ 135mph /217kph
0-100 kph 3.2 seconds