Level 3 is free and has no requirements other than to be bestowed the level due to experience at an orb or have it occur naturally given sufficient time, which is typically a few seasons to a year or more. The guild and temples give a 'shortcut' given the experience is attained.
However, as you may have noticed, there are other requirements for level 4, so keep these in mind.
-1000 silver for a silver plate each -A heroic act
These are not difficult as there are many silver plates and guards for instance are required to have silver plates to accept the job.
Think about what act specifically you might have done or will do to achieve this. Saving the children and getting them into Neverwinter was, for example, your generous act.
A heroic act is defined as: courageous, noble, or self-sacrificing action or behavior. Without this, you will remain at level 3 perhaps indefinitely without resorting to other, less savory, acts to force it.
This is partly why adventurers are regarded so highly, and someone such as Brutus would have fans and fame wherever he is known simply by showing his plate.
To be Orichalcum, he would have to have shown a mercantile act (copper), a generous act (iron), a heroic act (silver), a saintly act (electrum), a miraculous act (gold), a fate changing act (platinum), a legendary act (mithril), and finally a godly act (orichalcum).