It was the customer who suggested using the vacuum, to keep from having to go behind us and replace any lost insulation.
In that case I don't see where they are fussing from other than penny pinching. This all comes down to client expectations and clear written contracts
that if modified should be signed off upon somewhere. (edited in this piece **** I don't use written contracts for every aspect but I do use a pdf contract for all bat and bird exclusion and serious wildlife exclusion and clean outs. There is much to say and I want them to know what I am doing and not doing, you can even add spaces for them to sign off that they have read and understand. That said, many have run decades without a need for just a couple of written contracts and I'm sure they will chime in that it is largely unnecessary and they aren't wrong, just a different mode.)
Vinke is right about the aspects of work promised, versus work delivered, but if the client specified to change it up, I would have had them agree to that
beforehand.
I know in this case you probably weren't sure it would work till your tech got moving, so hard to see it coming.
I've struggled my first two years with client expectations and being sure that what I promise is met 100% of the time. While I always make them happy by the end, if you aren't careful it costs you more than you had planned for.
I find bird exclusion to be the place this happens most with those folks who are bugged by even a pigeon gliding over their home but not landing. You usually can tell after a few of these people and therefore make sure you spend extra time explaining.
In your case they should pay, whether it took you 45 minutes or longer, as they agreed to your price. I do my best to not discuss how long any job takes in great detail, as they can vary and I want folks to not focus so much on trying to determine my labor rate as that the job will be done correctly where it takes 2 hours or 24 hours, it is up to them to pick me over another contractor based on the bid and other factors.
Sounds like they just thought what you did was too simple to pay that much and if that is the case, imagine where a lot of things guys do for wildlife control would be if everyone just dropped their rate when the landowner said...
"Well I could have done that myself!"
There isn't an easy way to go really, you can decide if you think it is worth the client promoting you to others or if they have a written description and you didn't comply if they will use that to flog you with.
Bummer....
Justin