Post a floor plan to scale.

I have a friend with a tiny kitchen and she has a 24 wide counter depth fridge, 18 inch DW, and single bowl sink. She used a separate cooktop and wall oven as she was able to install the wall oven in dead space above her basement stairs. The fridge holds an amazing amount and is quite well laid out.  The 28 inch fridges I have seen are more like an apartment size fridge and don't have a particularly useful interior layout and aren't as tall. If you are doing a single wall kitchen in a tiny space remember that kitchen cabinets do not have to be 24 inches deep. I pulled my cabinets away from one wall so that side has an extra 5.5 inches of counter depth. The extra depth may not seem like much but it is very useful for me.