[kayge]

You can avoid all 5 almost* entirely and make amazing progress by doing bodyweight exercises at home, 2-3 times a week :) There are plenty of free guides out there where you can start at almost any level. E.g. can't do a pushup? put your knees down. Still can't? Do it at a head-up incline. Still can't? Push against a wall. Keep track and make progress until you can move to the next harder exercise. And always remember it's a marathon, not a sprint, so be patient with yourself.

* Can't make any promises. You might get hurt. You might need to pay for some kind of pull up system. But generally speaking: the sooner you stop looking for the perfect time/situation and just start, the easier it all becomes.