OK, so first off I think it depends upon your overall financial picture and plans. To answer those questions for myself, I paid attention to the folks at the bogleheads forum. They have specific ways to ask portfolio questions:
Asking Portfolio Questions - Bogleheads.org
They also have sections dedicated to withdrawal strategies:
Withdrawal methods - Bogleheads
I would encourage you to look at the withdrawal strategies and consider what method best suits you in your life.
It also depends a bit on tax structure of your country and your asset allocation.
What I did pre retirement was add up receipts every month to know exactly what we were spending. I also figured out expected taxes (US based here) and found it difficult to estimate healthcare insurance. If you do not know these figures for yourself, I'd suggest getting them figured out. Some people retire without having a handle on things, they go ahead and retire when they reach some emotional asset amount.
The withdrawal method comes down to personal values, acceptance of pros and cons for each method, along with your risk profile/tolerance.
Here is what we did. The method that most resonated with us was the variable withdrawal method.
Variable percentage withdrawal - Bogleheads
IT just made the most sense. With a high equity portfolio one can pull more assets each year. In good years one pulls more assets. In bad years one pulls the same calculated percent, but the dollar value would be lower. Portfolio likely to outlast us. The toughest part of this is needing a certain monthly amount to live on. Without a safety net emergency fund the portfolio withdrawal might not be enough to live on. Pre retirement we changed our focus from saving in retirement accounts to building our emergency fund. Many choose 3-6 months for this, we chose two years. In this manner we can handle extended bear markets. What will you do in your circumstances? There is really so much more to the story as it comes to retirement time.
What I did prior to quitting my job at an earlier age than normal in 2020 was to sell some holdings, the amount of which was based upon the VPW method. I transferred three months worth to our checking account (I quit end of September so the 3 months were for the rest of the year). I also sold enough to finance all of 2021, this amount sits in "cash" in a retirement account. In this way there was peace of mind to cut the cord and have enough money, NO WORRIES. At the end of each month, in addition to adding up expenses, I total assets, do the VPW math, and move another months worth into checking accounts.
Regret minimization can be a good thing to focus on.
Now, to do a better job of answering some of the points you raise.
Sell month or quarterly? Your call, can also do annual. Having funds set aside made this recent bearish price action tolerable. One has to plan in advance for the bad times, they will come again. In the future I will likely sell and transfer monthly.
Borrow on margin? Sure if you want to. I like the debt free peace of mind. Imagine if you did this when stock price was $900 and here we are at 660ish. I'd say emotional turmoil not for me in early retirement. I'm a fan of Elon but certainly don't mimic my investing behaviors after his.
I don't understand the valuata/NOK statement.
I ignore decisions such as what days or time to sell. Some months I do my receipts early, others late. I figure it all evens out. I refuse to agonize over every decision. FYI, this month I did finances early, as a result less money was pulled than if I waited until end of March. If you want to be sure to avoid start or end of market day emotions, set orders to sell at closing or VWAP price.
Volume Weighted Average Price (VWAP) Definition.
Who offers advice to go on Margin to fund retirement? I bet they are not older. No F'n way! Again, an individual choice with risks and rewards. I've had enough failure in the market to not want to feel bad with any further problems.
We had some mortgages and a finances M3. But if one goes full tilt with debt and margin, a bad market creates difficult spots to get out of. Emotions can create hasty moves. One might need to sell stuff just to sleep. While we sleep well, the emergency fund has grown large enough we are likely to pay off ALL debt in coming months. Debt to asset ratio can be an interesting metric to track. We retired with debt being <5% of assets.
In the big picture of things, I think the timing of buy and sell decisions can be very tricky to master. Large funds likely have to sell into bullish sentiment while share demand is high. They can then buy when sentiment is low, dropping the price further by dropping their bids. Perhaps keep track of how you view market sentiment, sell when prices are high, when emotions are very bullish. For example, back when TSLA was near $900, the 200 day moving average of the share price was MUCH lower. When share price is 200% of the 200 day average, I like to be cautious. But you have to be a wizened student of the market to make such moves.
What do I think overall? Eh, absent other evidence, I fear you might be retiring with more hope for leverage financing your lifestyle rather than a sufficient asset base.
