What is your percentage gain on the investments you are looking to sell?
The long-term capital gains tax rate starts at 0%, up to $44,654 for singles and $89,250 for MFJ. However, this comes after regular income; so if you work half the year, are single, and make $45k, then your LTCG will start at 15%.
It's not free money, but could be a significant dent in the business case to work part of the year.
You also, of course, only pay tax on the gains, not the full amount withdrawn. If you had a 50% gain and withdrew $200k, you would have $100k taxable. If you are MFJ, then with the standard deduction this could be tax free. It does count toward MAGI, though, so it would impact your ACA cost.
Is there a reason you are in such a hurry for a second house? Retirement is a major life change. I would suggest you rather stretch this plan to 3-4 years. This will give you time to adjust to your retired life, without making it more complicated so quickly. It will also, of course, reduce the tax hit.