Mate, if you need help with anything, don't hesitate to ask.  I will send smokie around with a box of Heineken.   

If he does at least we will know he has hit rock bottom and the only way he can go from there is up.

A lot of the mom and pop stores buy at Macro....may only make 3 or 4 baht.

English mate of mine lived in a village just outside of CR, him and his missus were both big drinkers.  Little shop there used to sell three bottles of Leo for what I thought was a pittance, could not have been making much per bottle.  But mate said you should see how much they sell every day there, it must add up.  They really do work on small profit-big turnover.

Depends where you buy from and how many cases you buy.

You forgot to mention the Chinese Middlemen who deliver all over Bkk.
They are buying it in bulk, hundreds of cases at a time, and spend all week delivering to your local mom n pop shop who cant afford to buy in bulk.
43 from source, sounds about right, a mom n pop shop buying from a middleman at 48 baht and selling at 55 baht sounds about right.

Mick, have you seen the mark up on cigarettes, buy a carton of SMS for 460 baht, sell for 51 baht per packet, or 510, the profit lies in selling 4 cigarettes for 20 baht, turn 46 baht into 100 baht in a day.

Another money maker is those shots of lao kao at 10 baht per shot, or sold in an M150 bottle for 30 baht, popular with the local motocy drivers and labourers.

Some of these local mom n pop shops are a goldmine.

Tops is expensive, i do not drink chang, so no figures, but rgs is correct the "chinese" local middlemen will undercut any supermarket.
What is more amazing is that you will find three or more in my locality with shops next to each other. They will not undercut each other.
You work that out.