The biggest question is, how long are the walls and what shape are they in? If they are somewhat in disrepair and/or have no rebar the 312 will pull them in no problem provided you can reach across to pull them in, if you couldn't, you could pile dirt so you can drive over wall to get at it. Most houses are 8" walls here and the 210 pulls them in without even knowing they are there most of the time, the odd 12" wall is no different, but most of the time there is little to no rebar in them. While it was not fun, I did one house demo with my 6 ton mini ex, no hammer pulled out foundation with very little issues. Once you have a section in the center pulled in, they go in quite easy (provided it's not winter and they are frozen). Once you got sections loose, simply dropping them on the floor will break them up into workable pieces.