Let's assume I haven't done a lot of trades and nor am I going to do. How can I build reputation?
Once a month I'm buying something which I need. So the only way to start gaining reputation (*read trades*) is by doing Escrow.
I can link my other jnr. account if required if that makes it more honest.
That is not how you build trust to do escrow. How does anyone else build reputation? You earn it over time by doing trades and being an active member of the community. Linking a Junior member account is still useless because it's a three week old account with no history. Not sure why you're so eager to start an escrow service either. If you're looking to earn money then there are much easier and less time consuming ways to do so. If you want to help out the community then do that by helping stop scammers etc but offering to do escrow when you're in no way qualified isn't the way to go about it.