By my very rough calculations, I am getting a difference of about $1860 per month difference between buying and renting, which adds up to a screaming $22k per year.
I have family who live in 4s ranch, and while I do like the area myself, I really dislike the mello-roos.
I recommend at least renting there and don’t choose a huge condo or house. Just choose a modest place. I’m sure if you showed your wife the hard numbers, she’d agree with you that buying a house at 4s ranch at this point of time is not a good idea. Continue to examine the numbers every year around this time.