Rewards: 49 Gold, R$49,000
Location: SEASON 2
Unlocks from: Owning Mazda MX5 (NA)
Maximum Required PR: 6.8

There are 53 events - 50 Trophy + 3 TT, and Progress Rewards split:
25% - 6GC and R$6,000      [PR 1.6]
50% - 10GC and R$10,000   [PR 3.3]
75% - 13GC and R$13,000   [PR 4.7]
100% - 20GC and R$20,000  

At PR 5.4 from the LTS you can sail past 75% and basically have the car for very little gold – LTS cost 46GC less 6 reward and 29 reward for 75% leaves just 11GC net cost (and of course you will have gained around 30,000 Fame for LTS+Series towards levelling up).
For series 100% you need to spend a further 46GC – pattern 5433343.  Upgrade costs are here