About a solid 0 lol, don't get me wrong, I'm not a crazy bitch who checks her partner's phone or follows them around because she's just overly jealous and suspects them to cheat at every given opportunity. Hell no. I just don't trust people in general and there's certain things that happened to me in the past that I would never tell anyone - I kinda live by the device: Hope for the best, prepare for the worst. If I don't tell anyone my 'darkest secrets' they don't have a chance to betray my trust either. I'm living pretty well with that so far. :)
Not gonna lie, I'm a 1. I don't trust anybody and it's hard for me to open up when I'm dating about the deeper things. I'm 100% myself mind you, my personality shines through, but my sensitivities and such you won't see until I really begin to get a feel for you.
I am quite open but not very open to people who don't seem trustworthy... As I meet people, I analyze them and their level of trustworthiness and then I am more open to those who seem like good people rather than those who do not. Also, if I do choose to date someone, that person already has to seem like a rather decent person for me to even go on a date with then.. so a certain level of openness is already there because I trusted them enough to go on a date or pursue things further.. So I'd say I'm pretty open - start at level 3 and based on the person, can go up to level 5. (or decrease if the person really shocks me, but never have experienced that)
Depends on the girl and how far along we are, though I have a pretty standard base when it comes to trust, in both romantic entanglements and people in life in general. if you don't earn it you don't have it.