using BETWEEN in WHERE condition

In Codeigniter This is simple Way to check between two date records ...

$start_date='2016-01-01';
$end_date='2016-01-31';

$this->db->where('date BETWEEN "'. date('Y-m-d', strtotime($start_date)). '" and "'. date('Y-m-d', strtotime($end_date)).'"');

You should use

$this->db->where('$accommodation >=', minvalue);
$this->db->where('$accommodation <=', maxvalue);

I'm not sure of syntax, so I beg your pardon if it's not correct.
Anyway BETWEEN is implemented using >=min && <=max.
This is the meaning of my example.

EDITED:
Looking at this link I think you could write:

$this->db->where("$accommodation BETWEEN $minvalue AND $maxvalue");