We currently own Suzuki Kizashi 2012 AWD.I will own the car end of year(loan ends). My wife stays home and takes care of our 2yr old son. Next year we are planning Pre-K and with 2nd baby plans we began to think if we need a SUV or another Car.
Our parents or in-laws plan to come once in an year for few months to help.
To make sure I understand:
You are currently a 1 car, 3 person family. You work outside the home and drive your car to work, currently your wife walks or takes public transit with the 2 year old.
When Baby #2 arrives you will be a 4 person family, but actually a 6 person family > 6 months/year. 6 people will not fit in your current car. Also, your 2 year old will start preschool and needs to be driven as there is no good public transit option. The grandparents did not help with the first baby, so this is new territory (or did the 5 of you fit in the Kizashi?). Also, grandparents will be flying in rather than driving, so they're not bringing a car of their own. Grandparents are unwilling to rent a car for months-long visit.
I think your option #2 is fine if the grandparents can drive themselves somehow. I'd also propose option #4, keep the Kizashi and get a second car (better fuel economy, possibly higher insurance costs?) for the few times you need to get 6 people somewhere all at the same time. They don't all have to be in the same car.