50-100 USD
Desert Eagle.
price depends on overall condition. check at GUNBROKERS.COM look under colt 25 cal. your pistol made about 1922
made about 1904
100-700 USD
Inexpensive.
about 1908
about 350 or so
Can't be answered without more information
25-100 USD
Most likely a small semi-automatic pistol
25-100 or so
Colt offers history letters.