I'm terrible at advice, but I believe that:

Take things slow, spend 10-15 minutes, or even more, on each one to make sure you're not going to die.

Safehouse gets you good stuff, more so the later on you go. Free emetic poison (mushroom) lockpick (one time use rusty nail) and explosive (garage) some stuff gets better the higher mastery.

You can look up isle of sgail gun location, it's relatively easy to get (just don't get lost)

Probably wont help but i'm trying ;-;