100-200 USD
50-150
Depending on EXACTLY what you have, it could range from 200-4000 USD
Put hammer on half-cock and & push rear of barrel to the right.
No
I'm afraid that is like asking, "Does a car have a tape player?" It depends on the make and model. Personally, I have a Colt .22 Model 3 derringer and it does NOT have a safety. But, I cannot speak to the many other makes and models.
You need to leave this to a good gunsmith.
no, just 45 long colt, what is was made for
made about 1970
Based on proofhouse.com, second model derringers in .41 cal with serial numbers 1-9000 were made between 1870 & 1890.
50-200 USD
about 1970
Priceless!