Is there any minimum period of time the first replacement property  needs to be held before using in a 1031.   

These provide stability and regular income, which can be crucial in retirement.Cash: 5-10%Keep some liquid assets for emergencies and short-term needs.Consider these additional points:Diversification: Spread your investments across different sectors and geographic regions to reduce risk.Tax efficiency: Consider the tax implications of your investment strategy, especially with your high net worth.Regular rebalancing: Adjust your portfolio periodically to maintain your desired asset allocation.Professional advice: Given your high net worth, it's advisable to consult with a financial advisor who can provide personalized recommendations based on your specific situation and goals.Risk management: Consider your risk tolerance and adjust the allocation accordingly.

Finally, unless it is a duplex, you cannot claim losses from house hacking, period.

Anything can happen: the market can shift, we can go into another extended lockout period, the property can be destroyed by a natural disaster or by vandalism, the list of contingencies is endless.

I would like to look at it over 10-year period.  

Make a habit of checking your competitor's listings periodically and when it makes sense for you, make upgrades and listing updates.

This deal highlights our efficient turnaround strategy, leveraging market knowledge and partnership to achieve a solid profit within a short timeframe.

Those little rascals can build nest in a very short period of time…  

If it’s strictly an investment, you may need to consider conventional loans or other creative financing options.Cash Flow Analysis: Do a thorough analysis to ensure that the rental income will at least cover your mortgage, property taxes, maintenance, and vacancy periods.

That isn't really efficient from a management sense.