Using free margin as a stop?

if you really are going to start a trade indenting to lose $100 better give to to charity, you gain better emotions

or use it to help with the cost of joining a trading desk

Using free margin as a stop? If your free margin reaches zero, you get a margin call.

Anyways, IMO very bad idea and very risky aswell.

Might work once or twice but eventually account will go bust.

Yes bro. About once a year someone has this idea and pops up the question. It's not new, but it's not widely known. You can of course, divide your capital into 10 or 20 parts and risk that part on a single trade.
TP or margin call. Make or break. Do or die LOL.
Now, the problem is there's too many hurdles for a practical application.
First, look how your available margin changes depending on your position size AND your pre-set leverage. Quite math intensive (at least for me LOL) to figure your possie size versus technical stop level (pips) Second, weekend margin policies might be tricky with some brokers. Third, even margin policies can be tricky with some brokers, ie. Oanda will start closing your positions when you're at 66% or something.

So, all in all it's like performing brain surgery, with kitchen gloves on. On yourself. With a teaspoon. In a dark room.
Can be done but you have to be quite careful.

I need a certain amount of equity just to enter in a micro positions. About 20 bucks. So, there's where you'll be getting stopped out. When you don't even have enough margin to meet the minimum requirements.