Fey and Erte, as LP has pointed out you are well within your rights to seek out alternates quotes etc. What I have learnt from experience in like matters is don’t tilt at windmills by yourself.
By this I mean talk to as many other owners as you can and get to know those that are of a like mind. The amount of support you have for any issue is crucial. Point out to others what you are trying to achieve.
For example point out that:
the painting needs doing or it will cost us more later!
I got a quote from a tradie that is 30% than the one the SM got us, why are accepting higher quotes?