To choose a place where they could reside for a long time, there were a lot of things that had to be considered.
Firstly, it has to be cheap. Benjamin was not so rich that he could simply squander money everywhere. Secondly, it has to be somewhere less populated, since nonconformity often brings judgment, so keeping a low profile was essential. And lastly, he needed a lot of space, enough to let everyone practice their magic.
This can be considered pretty demanding specifics, but fortunately the city of Rayleigh was unique. Without much effort, he managed to find the perfect place.
