Loong ago I bought the MMC 1911 front sight staking fixture. It wasn't low cost, but if you read and followed the directions. it did a quality job. I think they quit making it because after the patent ran out, it got badly copied by others.

That said, it exponentially increased the quality of the installation if you first machined a flat surface on the top of the slide for the sight to fit on. At least on Colts. It appeared that Colt simply touched the slide with a grinder. The spot might be flat, it might be perpendicular to the slide sides, but not necessarily both-or either.

There's a lot of folks who call themselves "gunsmiths" that are simply parts changers.