I just got to the part where they asked me to join them after completing the TradeCraft quest. I have saves to go back, but...... What I really want is to do as much of each faction as possible, before really deciding. I was told that a message would appear stating that this will affect other factions. I saw no such message, but................... Was this decision final?

And if it's not, then what quest within the rail road faction is the one where I have to really side with them?

It will warn you later in the game that if you take ta certain action, certain factions will become your enemy and there is no way back.

You can in fact be friendly with all major factions at the same time, just avoid the quests where you need to choose. Since it's general discussion thread I cannot tell what exact what to do. What you can do is to lookup factions quests in FO wiki and see how far you can go into MQ before it's too late. I have sparetime so I can post something in proper forum for you (and for others who may need the hints).

Cheers,

-Klevs

Desmonta ask me to support them instead of the minutemen, doing this does not look like have any impact on your relationship with the minutemen.

If you manages to become hostile with the institute, say shooting father, you can not finish as railroad,

You can be friends with everybody at first, its only later you will have to make the decision of who to turn on.

IMHO this is part of the game, you make decisions and based on that you get an outcome.

I understand the idea behind it, do one playthough with as many quests as possible. Your decisions are not based on the character but to get the most done in this virtual world.

Since your decisions are not based on roleplaying, but playing the game engine, you could also just consult the Wiki page as mentioned earlier.

p.s. being pure Railroad (and mandatory Minuteman) is actual quite fun. You get to do jobs for the Institute, while meeting with one of their Coursors (Cleaners) you can watch them fighting the Brotherhood of Steel and walk just between them without anyone shooting at you.

The Battle of Bunker Hill is interesting when your allied to all three as none of them will shoot at you first.....so much loot, so slow walking because I'm so overloaded.

I love the kill this coursor jobs from PAM

First he helps you finish off anything in the area and then you blow off his head... PAM said, as long as noone survives the cover is intact (with a 1.24% possibility of discovery).

This. I was looting RR, BoS and Institute corpses. It wasn't until I went into the sewers that I actually had to attack one of the factions, and apparently since I killed them all down there (whichever side I hit) no one above ground new about it. I could slaughter a dozen BoS in the sewers and the BoS above ground still thought I was their best friend. Awkward.

PS - I added spoiler tags and then the thread gets moved to spoilers.