Free Shipping As "pickup From Store"

I am trying to add a free shipping option to let users choose if they would like to pick their order from the store themselves. But with a lot of searching and reading from the KB I couldn't find a way to do it.

As far as I can see that one city could have only one shipment method available (which is actually ridiculous when you consider carriers could be "changed". How could you change something while there is only and only one option??)

So how can we do that?

does this help

http://prntscr.com/gj3bbc

Thanks. That's what I've already done but it doesn't show up in the carrier selection list. I mean option to collect from the store is not avaiable to the customer, not visible.

As per KB refers, it's not possible to add two different shipment options per location. I actually don't have "locations", I use all the country at once; because there is no need to it here.

Edit: From the cart I can select "pick up from store" option with free shipping. It applies to the cart; but when I click the pay button, then the pick up from store option is lost and customer has to pay for the only available carrier.

works for me

http://prntscr.com/gk8xw5

Thanks again.

Here is what happens for me;

On cart; https://prnt.sc/gka2bt
I can select the "pick up from store - free shipping"

Then on payment; https://prnt.sc/gka1tw

You can see the there is no selection.

Please make sure that the Use for free shipping setting is enabled for these methods

http://prntscr.com/gkj3ds

It's already enabled and no shipping cost is defined.