The guild can be level 1 however I have heard of guild's gold wiped alongside player bans when being caught botting, and from what I have seen this happens much more often with a level 1 guild that has no members. Higher level guild with members gives more credibility it wasn't made as a safehaven for your gold. That being said, you don't want a bunch of random people seeing an insane number of achievements from botting popping off in the guild log so try to keep it only to friends.
All of that being said, with 45k youre not a farmer so you don't have much too worry about; just something to keep in mind if you expand in the future.
