Well, for 38 years in the Army, I used a pre-Series 70 Colt Gold Cup (SN 10XXX NM) as my duty sidearm with total success! At one time, as a member of a pistol team, I fired over 500 rounds of GI hardball per week thru the thing for over a year, and all I ever had to do was to replace the brittle roll pin that the rear sight leaf pivoted on. It was too brittle for hardball and kept shattering. I finally replaced it with the shank of a Herter's fish-hook, and that never broke. I later put a Wolf 26# recoil spring in it when I was using hot handloads in it. I gave it to my daughter, and it was in as good shape as when I bought it in 1964 at Frontier Sporting Goods inFairbanks, AK.

I guess the amount you spend (=the degree of custom work) on a handgun would depend on the use you intend to put it to. A RELIABLE M1911 with a decent trigger does NOT have to cost a couple grand! If you are looking for X-ring accuracy at 50 yards, it will cost a little more!