It would seem to me they could quickly eliminate 99% of the documents from inspection.

[mackdaddy]

This "Special Master" would only look for any documents that would possibly be first belong only to Trump.

Nearly ALL of what is in these boxes belong to the US Government through the National Archives. This is a 40 plus year old law through the Presidential Records Act. He took what did not belong to him.
So they should be a quick NOPE for any Personal privileged for Trump

ANY Classified documents.
ANY Official White House Documents.
ANY Other official Government documents and communications.

So we are down to: any truly personal individual document that were mixed in with what was above such as his passports or other personal documents.
The if there is any communication with a personal lawyer (and not office of the president lawyers) those should be gone through because even those should be evaluated by someone for a "crime fraud exception".

If the judge had limited her order for a special master to only the second group and released the items obviously belong to the national archives then any "special master" would not have to have "Uber Secret clearances" to even look at the cover sheet.

Trump had as much right to keep stuff from the Whitehouse as he does to take the towels and TV from a hotel room he stayed in. He STOLE these things.

[FBaggins]

1. Unfortunately- it isn't nearly so simple

It’s mistaken oversimplification to think that the presidential records act means that former presidents can possess nothing from their term(s) because it all belongs to the government.

The gray area between presidential/personal has been debated for decades and even came up with a case where republicans were trying to get archive documents from Obama after he left office (and lost)

[sanatanadharma]

2. Trump can have the press clippings

It is as though Trump sat at the dinning table with press clippings and top secrets and piles of mixed papers piling up, until aides brought a box, plopped the pile in the box and put the boxes aside to make room on the dining table for more top secrets, press clippings, and boxes.

When the White House squatters vacated, they grabbed the boxes and tossed them into the moving trucks.
When the FBI grabbed the boxes, they found that the press clippings mixed with the official government records, essentially dated the creation of the table pile.

Top secret nuclear secrets' papers found in boxes with press clipping dated from ? to ?, suggests the time period wherein Trump kept, stole, failed to return the classified hard-copy as required by law.