Short run of propane to stove and tankless WH
What I ended up getting was a hose with a regulator.  On the other end was a 3/8" flare female.  I found a 3/8" flare male to 1/2" MIP (Male iron pipe).  I used a 1/2" coupling to a 3" nipple to a tee.  From there it went to each of the 1/2" nipples through the wall, to a street elbow, and finally to a gas shutoff valve.  This is the basic setup now.  I'll have to order a changeover for the 2nd tank.

street elbow =&gt; shutoff         street elbow =&gt; shutoff
|              ---------        |
|                wall           |
|              ---------        |
|__________________Tee__________|
                    |
                    |
              1/2" coupling
                    |
        3/8" male flare to 1/2" MIP
Regulator with hose 5/8" female to 3/8" female
              propane tank