re: Portable Generator pigtailed to box

Interlock kit will require the specific kit to your breaker panel.

You'll have to move some breakers.

The generator breaker to the twistlock outlet will need to be up top by the main for it to function.

I've installed a few for people. Depends on the outlet mounted box whether it hangs from the box via nipple and knockout or its conduit over from brick.

I install the plug/box with tapcon masonry screws and epoxy.

60-80 for the box and plug combo. Takes me like 2 hours once install starts depending on conduit run and length.

So I'd guess $100 for box and interlock. Wire is by the foot so that can get pricey. Used to be about $60 for the wire. $20 for the double breaker if it's a GE and not a square D or something high dollar.

$2 hours labor (its $135 hr here for a plumber right now... not sure about electrical. )

How far away is the plug in for the generator to your panel will be the main driver. Wire is priced per foot.