I stopped at a planet on my first turn and the encounter card I drew offered me to buy a ship for free after spending a reputation point (which I could) but it also required me to lose fame which at that point I had 0.
Could I have purchased the ship, can you spend fame (or for that matter, repution) for a reward if you are at 0 (or negative reputation)?
I could not find any rule that said I couldn't, usually FFG rules make a point of specifying you can't spend if you are at 0. I could only find a rule that said if you lose fame when you're at 0, it stays at 0.