I ran the same numbers and used the same rationale but please don’t apply my purchase to the O.C., you still have a ways to go. Use this formula, when P&I of the full purchase price is equal to or less than rent, then it’s time. P&I on 550k is 3500 at 6.5, you still have a third to go. I use the P&I since tax offset is about equal to the tax and insurance and use the full purchase price for calculation, not the loan after down payment.
Factor in the difference between your rental and your purchase, they may not be equal, figure out what the rent would be if you rented the same house you plan to buy. In my case my P&I based on purchase price is about 1700, 200 more than my rent, but the purchase house is double the size so I had to factor the rent of the house I was purchasing, which was 2000+, since I was under that, I pulled the trigger.
Wait for 350k based on the numbers you quoted, the financial world is falling apart, it will get there.
There is an old saying about the mortgage tax deduction not being the savior some make it out to be. “Paying $1 to the government is still cheaper than paying $3 to the bank.”