I doubt he would have a problem with a gassifier like a TARM/GARN/Woodgun/etc. Usually the localities that have ordinances go after the EPA exempt outdoor boilers that smoke up the neighborhood. you cant even tell when a gassifier is running from outside as Im sure you know from experience

I think the bigger concern would be getting a good wood supply at a reasonable price in an urban area - urban dealers are usually ripoff artists and there are few scrounge opportunities.. Might need to get a splitter and look into buying grapple loads of logs.
Man Id love to go off grid too but hate the thought of solar panels on an old house roof... wish I had the land to put them off someplace in the back 40.
BTW, Greg I had no idea you were a serious woodburner too. Are you a member over on hearth? I think a few of us here are....