That is going to depend on the type of competitions you plan to enter. My brother is a silhouette shooter and his requirements are totally different from those shooting the IDPA (International Defensive Pistol Association) matches here. The local IDPA matches happen to organized and run by a woman, by the way.
I may have more friends in Cowboy Action Shooting than in anything else and again, what you would use is different from the other types.
There are many other categories of pistol shooting, some of which are compatible in terms of equipment, but some do require something specialized.
My only handgun is a .44 caliber percussion revolver that is cheap and fun to shoot but miserable to clean. I claim to shoot a pistol for fun, but a lot of that has to do with not shooting one well.