I have question, how can anyone start his own escrow service. Where do you get that kind of trust
Usually, you gain reputation with the time as you do trades, help the community, etc... Then, when you are a known (and trusted) member of the community, you can decide to start a service like this one. There is no formula to get a reputation.
whats the most trustful "institution" which still can be anonymous?
Idk.