Stepping outside isn't the end of the world, it's just that getting back in usually isn't easy. You should always know how to get back into a safehouse before stepping outside, or else make sure to start looking for a safe place to sleep once you're down to 10 AP (15 if you're cautious, and if you aren't cautious you probably aren't going to survive long.) If you run out of AP outside you are dead meat. I used to go days without stepping outside, only venturing out to revive people standing at revive points. If I weren't such a dedicated reviver, I probably would have avoided stepping outside ever.
Anyway what nodaisho said, the necessity of Freerunning isn't really to avoid stepping outside, it's to gain entry to EH (extra heavily barricaded) buildings. The tricky thing is you can't freerun in off the street, you can only freerun from one building to another. So you need to find what are referred to as "entry points," a building with VS (very strong) or lighter barricades.
Hm. Now waiting for a revive at the designated carpark in Lerwill Heights. Considering the pros and cons of wreaking zombie havoc for a little while?
Well the main con is that it'll be boring as hell at first. If you wanted to go the zombie route you should save up some XP first so that you can buy a couple skills when you switch sides. Without any zombie skills you'll barely ever hit, and it'll be hard enough just finding someone to attack since you won't be able to break into buildings. It's depressing going for days where you just wander aimlessly, maybe scratching ineffectually at some barricades, accomplishing nothing.
Revives are usually fast though (well they were when I played anyway, don't know what it's like anymore.) There are lots of people like me, who just dedicated themselves to reviving people all the time. Usually you just stand at a revive point and then come back in a day. Heck, if you're at the carpark then you'll probably be revived by someone from the Sebright Union, possibly one of my old buddies.
So is scout best to start as then, or should you start as something easy to get XP with and then take free running? I'm thinking I will start as a firefighter and take freerunning first chance I get, followed by hand to hand proficiency.
Starting as a scout could work, but you'd want to scrounge up some useful equipment as the first thing you do. I would suggest freerunning into an NT building and searching for a DNA Extractor, because gaining XP through combat might be hard for a scout at first.
That said, starting as a fireman is probably a faster way to build up. You'll be better at combat right from the start, and it won't take too long to get Free Running.
THAT said, it really doesn't matter because within just a couple levels you'll have the exact same skills either way, so just do whatever appeals to you more.
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It's kinda sad how much I remember when I haven't played in years.
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Actually, what's even sadder is that I still remember most of the rules to Dungeons and Dragons. At least the 2nd edition rules, which is the last time I played it (for reference on how long it's been since I last played it.)