If it`s not written on the contract, it doesn't matter what they have told you verbally. If there is work that you need done, make sure it is in writing and written in a way that guarantees you haven't misunderstood or been mislead about what they are doing.
Approximately 3 1/2 years ago, after already having had my main drain snaked by the same company, I understood that I was contracting to have residential portion of my main drain replaced. The entire residential portion. I didn't live there any more, so rather than snaking repeatedly, I wanted the problem resolved so that I wouldn't have any tenant emergencies.
When they did the work, they told me that they were not responsible for the city portion but assured me that if something went wrong with that, I just needed to contact the city. They told me that their work was warrantied for 25yrs.
Both of these things are true. But the misleading part is that while I understood they were replacing the entire residential portion, they replaced all but 1-3 feet, and since the contract says "approximately 5 feet" and doesn't specify "to property line" or "connect to city portion", I had no recourse when their camera inspection last month (for which I paid $190 plus tax) showed that the remaining residential portion failed. They quoted me an additional $3400 to do that work (but if I'd agreed to it, would have made the camera work of $190 free).
Now, years later, they don't remember the conversations about the original work. They don't remember me. I've never previously had a main drain replaced and in fact I've never previously owned a rental home so I remember the decision making-process very well. I know that when I agreed to have them dig up my front yard garden, it was with the understanding that this was going to be the end of my main drain worries failing some kind of natural disaster. Do you know how long your main drain is? If you wanted your main drain replaced and they wrote "approx. 5ft", would you think to ask whether it's possible that it might not in fact be 6-8ft long? Of course not. Would you know that if it's not stated that they are connecting to the city drain, they aren't responsible to do so?
When I asked what they could do to remedy the situation, they offered me $20 off snaking the drain.
I ended up getting that work done by another drain and plumbing company for $1400 plus HST (note that that's $2000 less than this company). This time I made sure that the job description stated that it would be done all the way to the property line.
The initial snaking and camera work done the summer prior to the main drain replacement fine. And the part that WAS replaced is probably fine too.