Hi there @Arijana79
Well done you on what you have achieved so far! You've obviously learned heaps and improving all the time. That's all any of us can do really.
Clearly you are priced right and have the basics sorted. Suggest if you haven't already, indicating the lift/level 7 in your listing under 'things to know'. Those with heavy luggage need to know this.
Lots of fine suggestions below, including figuring out if you are targetting families or not. If families to get longer bookings or couples, then you've already figured out to replace the single beds. Go for a queen. Also check you have enough cutlery crockery and kitchen appliances. Just make sure you get the basics sorted.
I did notice the cooker is next to a curtain (fire hazard), and perhaps if you changed the sheer curtain to blinds, it might actually open up the space more. And i'd never have kettle on top of microwave right under a cupboard - the steam from the kettle will damage the cupboards eventually. Could you do anything with the tiles? Like regrout or paint over? It could make a massive difference. Kitchens are important to airbnbs and I look at them when evaluating a property even if its a kitchenette. I also saw some piping around the cooker, can that also be painted to blend into the white wall? If you were able, perhaps replacing the kitchen table and chairs with something that isn't white (so easily stains/chips) and not padded (who knows what's been wiped on them - puts me off). A nice wooden kitchen table instead of what you have that looks like a dining table stuffed into a kitchenette.
Some nice decor that represents the vibe of your city maybe on the walls. Lots of great wall space to do something with. If you have lots of natural light, then indoor plants always helps.
I think professional photography if it's not affordable for you, can be done by following the tips airbnb provides. I take my own photos, i just take lots of them in different light settings/time of day with all lights on inside and see what looks best.
Hope this helps,
Kind regs
Mary