Hello,

Have you read all the "ref (question 73484)" ? 

Because, the solution is there ! 

pos.company is not a browse record from the company, it's just a var created by pos.

So if you want street, street2, zip, ... you need to had these fields when the var company is instancied in model.js 

{ 
            model:  'res.company',
            fields: [ 'currency_id', 'email', 'website', 'company_registry', 'vat', 'name', 'phone', 'partner_id' , 'country_id', 'street'],
            ids:    function(self){ return [self.user.company_id[0]] },
            loaded: function(self,companies){ self.company = companies[0]; },
 }

Next, you can add your modification in xml  ...

Address: <t t-esc="widget.pos.company.street || 'street undefined'"/><br /> 

# UPDATE 1

Need to add state_id[1] in the xml (state_id is an array with [0] = id and [1] = display_name)

State: <t t-esc="widget.pos.company.state_id[1] || '' "/>