quoting @maizefolk
Please do come back and post what you learn from your experimental loan.
~snip
Will do. Maybe I can throw down a few bread crumbs for my fellow noobs.
[/quote]
An update. TL;DR it is fine.
This has been a little bit of a trip. Touching the bases:
I opened the account at IBKR and arranged for an immediate transfer of some AAPL securities to fund it at the same time. They did not hassle me about being retired (saw that on another thread about IBKR) and they accepted my application within a day.
I transferred a large slice of AAPL which took about 3 days. I left some shares in the Vanguard brokerage so that my basis on what I moved would always be readily available since the ticker name is still right there in the account ready to be clicked on, no need to later try to clumsily retrace that history. Also, before transferring them I copied all the available basis information and printed it as a further safeguard.
After a couple weeks of letting everything settle out, I checked to see what the "withdrawal" portal said. It declared that I could withdraw about $9K. This seemed bizarre to me. I didn't know if it was because the account was just a couple weeks old and I hadn't passed the 30 day security bar that MMM mentioned in his original post, perhaps they allow only a portion of borrowing based on how long I have been a customer. Nonetheless, $9K got me nowhere so I just let it sit and didn't request any funds.
I then sent a deposit of $100 over to IBKR to see what happens to cash-- do they zap that amount for the $10 monthly fee on a Pro account? Or just take it from the AAPL quarterly dividend? Answers from their site are elusive so I figured I would try it. Their robots freaked out about the cash deposit and wanted to know what my net worth was again (which I had put on my original application) and how much liquidity it had. The robots said my funds would not be available for withdrawal for some number of days. All very robot like. 3 weeks later it is still sitting there in full so there is no indication of how the monthly fee comes out, and I don't know how IBKR's new policy change of no inactivity fees affects it, either. I am not sure if my Pro account is now free or what. More to learn.
I applied for a HELOC at my bank at this point, my home is debt free. I figured it might be handy to have available if I needed to quickly zap some money around. 3.74% rate.
Last week I checked again at IBKR and the withdrawal box said I could borrow well over $100K, it noted right up to the 50% Reg T margin. This was not yet 30 days after opening the account but they seemed to allow it.
I waited till the whole HELOC thing was settled and then did some math on the difference between the IBKR rate today of 1.6% vs. the HELOC 3.74% over the short term I want to borrow (just till December's annual stock selling harvest time) to decide which way to go for what I need. Is it worth it to dick around with margin when I have the well understood HELOC available?
I decided yes it was, partly because I am learning something new and partly because when my credit union contacted my insurance company for info they asked to be noted as a lien holder for a mortgage in case I ever draw on it. That brought home to me that I don't want a fucking mortgage ever again and (duh) that is what a HELOC is even if only for 5 months.
So between the lower rate, learning something new, not wanting any debt on my home, - and frankly - feeling badass that I have a huge lever to do wonderful things with the power of my money, I requested the full amount I need from IBKR today on margin. They instantly approved it and said it will hit my bank tomorrow. It is only 25% of the AAPL stock value so I am well within the zone of safety so there will never be a margin call. In the meantime, AAPL's stock price has climbed upward 9% in the month+ since I started this so with that general vibe I should never have to worry about it. Obviously I will be checking on it and will see what happens with their quarterly earnings coming the end of this month. One intangible price paid for margin is having to keep tabs.
Final thought- in looking around the interwebs I found that Chuck Schwab had a better explanation of margin than IBKR, with clear statements about how the repayment works. Nice of them. Too bad I will never have an account with Schwab again because it was the first place we ever had an account and those sumbitches would zap us quarterly with a "minimum balance fee" of like $25 because we didn't have $25K in there, just a young married couple starting out with investing. This was during the time when every trade was something like $30, pre-internet and pre E-Trade magic that transformed everything. I never forgot that they charged that fee and now that I am a multi-millionaire I will never give them a nickel of it. Just bitter I guess ;)
https://www.schwab.com/resource-center/insights/content/margin-how-does-it-work