You have 1000 and buy 2000 worth of stock using 50% margin. You dont get margin call with stock price decrease?
there are maintenance requirements. you will receive a margin call long before it drops 50%. https://www.sapling.com/6522069/calculate-maintenance-margin
You have the stock don't you? So you use the put as a hedge for the stock... that was your initial question. If the market rallies you make money on the stock... but lose a bit on the put. If you want protection you pay for it in insurance... you can't have it both ways.