I find it more likely he was going to rob a bank than he targeted Planned Parenthood. I think he ended up there more by chance than design.
When the shooting started, the PP folks disappeared behind a locked door and bullet-proof glass. The shooter, meanwhile, found himself facing the CSPD, at a distance, initially. The shooter was really lousy at planning. If he were competent, he would not have done it.
PP had moved from a location in Old Colorado City, due to protests.