We are planning now for our September build. I am planning on running 125' of 1-1/2" poly yellow pipe with two steel risers. The cost of anything over 1" becomes a lot more expensive for some reason. Not ridiculous, but, noticeable.
I need to measure it but I would be adding the new line where all my other gas items (furnance, H2O heater, dryer) meet because that is the easiest spot to tie in. The distance would be about 40' or less but the specs say 1" good for 20' or 1-1/4" for 100'. I would just like to run the small line due to cost but the 1-1/4" CSST would take care of it.
Don't remember the meter size but the gas company said it would handle it.