The carpet fitters have pointed out that the door in our living room will need trimming and they won't do it since it has glass in it. They reckon about 5mm needs to be cut off. I don't have a circular saw and can see most videos online would use that. I wondered if I could get away without buying one... I have a multi-tool (this one) and did wonder if the circular attachment might do. Failing that, wondered about buying a cheap smoothing planer (but never used one before). Reckon either of those would do the job or any better suggestions? Here's the door - not really sure TBH if it's hollow at all inside: Thanks in advance.