Laravel. Get single column values of a table using Query Builder

I have a table named "items" and an input for the where condition named "ref_code".

$items = DB::table('items')
             ->where('ref_code','=', $request->ref_code)
             ->get(['id', 'ref_code', 'name','price']);

But I can't seem to take the values of each column.

I checked wether the query builder worked or not by using:

return $items;

Fortunately, there's no problem.

But returning or getting a single value doesn't work with:

return $items->id

Is my syntax wrong? All of this are inside my controller.

EDIT: I tried

dd($items);

before returning and it showed me this:

  Collection {#325 ▼
  #items: array:1 [▼
    0 => {#322 ▶}
  ]
}