Execute 1 and 2 before retire,
1. get a HELOC of 200-300K. (3 days notice withdrawal)
2. Re-sturcture your mortgage portfolios if needed.
3. Might not want to sell CA property because of Prop 13 and paying gain tax.
4. Put $100K in saving/money market with 1% interest. Same day withdrawal.
The $500K can be in bond, stocks, REIT(public or private) or Real Estate Fund.
It depends on your current asset allocations.
It seems your real estate exposure is high, then
The $500K can be in stock market index 50% US index such as VTI or SCHB(the fee is lower than Vanguard)
30% in International index SCHF and 20% in emerging market SCHE.
Or you can build a 12-month or 3-year ladder of fixed income portfolio.