We did this with ours, they replaced the railing due to a few marks from the install, and a few other various items since jana was anal about everything.
If it's brand new, as in, you are the first owners? Look for loose railings on the stairs, paint out of place on trim, parts damaged from install, basically anything you might expect to see fomr the inital build being half assed.
Also ask if they did any work that might of required a permit, like lighting and such. just so you are sure electrical and plumbing and such was done correctly is it was messed with. That's your right to ask.
that's gonna be your call. the walk though could be something that you just use to make sure there is no wall damage or antyhing else major. little shit will delay the process
