How Much Home Can We Afford?

Myself

• Salary: 165k
• Net: 7.1k/month (after maxing 401k & HSA)
• No debt

Partner

• Salary: 66k
• Monthly Debts
  • Car Payment: $340/month
  • Loan Payment: $500/month

About

• HCOL
• 20% down payment
• Total House Cost: $650k - $700k
• No kids but likely in the next 5 years
• Pretty reasonable with groceries and eating out
• Wedding this year
• Assume market (~6.5%) rate, 30 year conventional

We're thinking $3,600 monthly payment (PITI) is pretty safe. How tight will $4,000 feel or even $4,400 feel for us?

Thanks in advance.