Buying a Car with Relocation in Sight

Hello People,

My current car lease is coming up and we need to buy a new car. Living in Massachusetts right now but will be relocating to California in 1-2 months. Relocation policy allows moving car at no cost to me. With the current car situation its anywhere from 4-6 weeks to get a car so do you think it is wise for me to wait till I move or buy the car now and then ship it?

I am thinking of following aspects,
1. Sales tax situation, will there be double taxation if I buy in MA and move to CA?
2. Registration in MA and then title transfer from MA to CA, is this process complicated?
3. Any other advantage or disadvantage of buying in MA or waiting to buy till we move to CA?