OP back. So, finally I received a paper bill from WasGas and wanted to report back here (for anyone's curiosity?)

First, they agree to the install-payment, so I don't have to make a full payment at this time.
Second, it appears that due to their "upgraded system?", they weren't able to roll back to the original service date, therefore WasGas charged me from the oldest date they could go back in year 2015. In another words, they let me get off the hook from paying the service fee in 2014 and partial 2015.
The grand total came out to be a bit less than $1000. I will make sure that to know what utilities I am responsible if I ever make another move to a new place next time.

Anonymous wrote:As others have mentioned, WashGas in particular implemented some "improvements" to their billing system that were an absolute disaster, even for customers who had had online billing set up for years. I can't remember when it started and stopped, but there was definitely a stretch of 6 months-1 year when I got bills erratically or not at all.

So: I could totally see how they might have failed to get your account set up properly. I would strenuously resist paying any late fees.
As for usage--for my smallish brick SFH, my bills run about $100-$150 in winter months and $20-$40 in summer months--last 2 years were in the $800 range for the year as a whole.

Same here....this month their billing system seems to be messed up again. I have not gotten a bill but the online system says I am negative billed for last month so I guess they owe me money. No idea how they are still in business.