Thanks .. I guess I'll wait until Season 2 and then have another lookEvery car costs 12$ and every track 15$ +VAT. You'll get a discount for three and 5 things you buy ( I think it's 10 and 15%). If you own 40 cars and tracks, the discount is 20%. Plus the fee you need to pay for the iRacing service. That's roughly 10$ each month, but there are always discounts if needed.
What cars you need? Of course the cars you want to drive or the team is driving for a special event. Sadly the 991 and the Audi are not extremely competitive atm, but I think that'll change for season 2.
What tracks you need? Of course the ones for the special events https://www.iracing.com/specialevents/ (the next one for example is Sebring 12h) or what's next on the ELMS schedule.
It's hard to tell atm what track you need, because season 1 is almost over ( 1 week to go) and the schedule for season 2 is not out yet. I'm sure it will be out during this or next week.