If you buy the boiler then you are responsible for the warranty if it doesn't work out of the box or breaks-down, the installer would be right to charge you for any problems.
As said before, a quote should include the total job.
It should include a spec of what they are fitting etc.
For example.
Brand A boiler.
Remove old boiler and dispose of any waste.
Flush the system.
Add inhibitor.
Upgrade Gas supply if necessary.
Fill, test and commission the system.
Explain the control.
Make good where necessary.
Leave in a safe working order
That will be £200000 please.
As said before, a quote should include the total job.
It should include a spec of what they are fitting etc.
For example.
Brand A boiler.
Remove old boiler and dispose of any waste.
Flush the system.
Add inhibitor.
Upgrade Gas supply if necessary.
Fill, test and commission the system.
Explain the control.
Make good where necessary.
Leave in a safe working order
That will be £200000 please.