Gardall or Amsec. B rated safe at least. TL is a bit overkill if you are not putting highly valued items in but is good due to weight. The 15 in TL15 means it is 15 minutes for tool and torch resistance which is in the hands of real people, not your run of the mill idiot thieves. TL30 is 30 minutes. TLs will be about 1k lbs vs 200 to 600 for lesser safes. Your regular gun or fire safes are what is easy to get into with just a grinder or pry bar. What ever you go with It needs to be hidden and bolted to ground. If thieves find it or devious acquaintances know about it they will zero in on it and really work to get it open, but once again TLs are on another level and I’ve seen thieves drag them out on pavement/roads attached to their car so they can get it to a place with heavy equipment.