Seeing as this is a rental, do you have a budget? glass tile can be pricey...you may want to put less money in...not familiar with slate tile for a counter...can it be fragile? I would think durability is key in a rental. Perhaps formica/wilsonart might be a better choice....

I would stay with white and beige or brown to keep a consistent color story throughout the condo. If it's in the budget, I would install a quartz composite countertop, easy to clean and maintain, hard to damage.

The slate tiles would be for the floor. The glass tiles are fairly inexpensive, and since that would just be used for the accent we won't need too much. We will do laminate for the counters.

But you think the decorative tile should be in browns? The dark grey would clash?

How open are the spaces to each other....if it's an open space then it's better to keep the colors consistent.

Here are some photos of what it currently looks like.

What colour for the decorative tile would you suggest?
Earth colour for sofa/chair?
For the counters we are thinking to do something dark to offset the white cabinets.

Here is a link that might be useful: Ski Condo Pictures

Pictures are so helpful. You have lots of gray in the stone on your fireplace so adding slate floor tiles to the kitchen, especially if they have some of the copper/brow streaks, would be a nice tie-in. I'm still a little hesitant about the glass accent tiles in any color. I think they look trendy and modern while your condo seems to lean more toward a rustic look. Perhaps you could find some tumbled slate accent tiles that would fit better with your overall design. I did a quick Internet search and have linked a page below for inspiration. I don't know anything about the specific site. Choose the counter top color after you decide on the backsplash. However, it's not a large space, so I would keep the counter color lighter. They don't have to be white, but maybe they could be sand, a lighter caramel than the carpet, or a light grey. That way they would provide some contrast to the white cabinets, but wouldn't weigh down the room.

Here is a link that might be useful: Backsplash Inspiration