純粹為了省稅或延稅，不值得；剛好有自住的需求，有延稅的好處。

Example of how to effectively combine Section 1031 and Section 121 for tax savings

Suppose that, in 2022, you and your spouse use a 1031 exchange and buy an investment property in Miami — a lovely single-family residence. You rent out your replacement property for the next four years. After that, you retire and want to live near the beach. Lucky you, you have the Miami property, so you move into it. Six years later, you sell the Miami property.

When you first did your 1031 exchange in 2022, you deferred $100,000 in capital gains taxes and $50,000 in depreciation recapture taxes. Ten years later, your Miami property appreciated another $500,000 before you sold it. Your total capital gain, including the previously deferred amount, is $600,000 (plus you still have the $50,000 in unrecognized recaptured depreciation).

Normally under IRC section 121, a married couple filing jointly could exclude $500,000 of capital gains. However, since you converted this property from a previous 1031 exchange replacement property, you will not be able to exclude some of the gains based on how many years you rented the house. 

You rented the house for four years out of ten years of ownership. Thus, you can exclude 40% of your capital gains under section 121. You must recognize $240,000 of capital gains (40% of $600,000), and you can exclude $360,000. You must also acknowledge the $50,000 depreciation recapture from the old property. 

Had you held the property for 10 years instead of moving in, any sale would have triggered the immediate recognition of all $600,000 of taxes plus the $50,000 in recaptured depreciation.