The inherent risk of borrowing against your bitcoin is done with a centralized exchange. I used Nexo last cycle. You deposit your bitcoin and are able to put it up as collateral at a certain rate predetermined by them.

You can then buy more bitcoin. I like to withdraw that bitcoin for safety purposes. The bitcoin you use as collateral is locked up. But as the price in dollars in reuses it becomes possible to pay off you dollar denominated debt to get your initial investment back.

And this is only done if you know where you are in the cycle. So that you don't get liquidated. Because this is how you play margin. You don't want to get margin called and lose money.

Also, don't deposit more than you are willing to lose. This is a gamble but it's an effective way to uncrease your stack and not paying taxes. The govt can't tax debt. Even if the debt is to your self.

I did it last cycle because I wanted more bitcoin. But it isn't worth the risk. I got lucky and came out 5x what I had. But I did get liquidated and it was a major learning curve and lesson. I was also a shitcoiner then. Not anymore.

The usd ebbs and flows like the bitcoin price. If you understand cycles and risk mitigation you can make it work. But there are always black swans to contend with.

The third is very risky. Just do 1 and 2😉