Haha just stating facts, Thais will happily cheat Thais when it comes to cars and money so farang have got no chance. And yes I live in Thailand happily married to a Thai.
Do not under any circumstances buy any vehicle without the book in hand. Walk away. The book is the collateral for finance, gambling debts, loan sharks etc and Thais are professionals in lying as to its whereabouts.
I recently used isaanlawyers.com for prenuptial and usufruct and had excellent service. The owner is Canadian. I've also seen siamlegal recommended by many people.
The Only prenuptial that would stand up in Thailand would be signed in Thailand. A prenuptial signed in Australia would have zero effect on Thai assets chased under Thai law.
Some of the high end shops are open if you fancy a new Rolex, but all the "normal" shops are closed and boarded up. I blagged a ticket for the lounge last week but even that was serving very basic fare.