80% of what is called 'luxury apartments' in Dar Vumbi belong to lower middle class estates in Nairobi.
Your prices are just expensive because there are like 5 total proper luxury apartments in Dar.
This is a $3500 "luxury apartment" in Dar. On the first floor no less. Small rooms, cheap ugly finishings, cheap AC hanging on walls.
For the same price, in Nairobi you are paying for views and space first. So, that's probably 25+ floor penthouse.
This house cannot rent out for more than $800 a month in Kilimani or Westlands.
View: https://www.youtube.com/watch?v=k4uO9iww0mI
What you get in Nairobi.
Broadwalk Apartment $2,700 a month (Your Dar Vumbi $3500 apartment does not even come close).
View: https://www.youtube.com/watch?v=pqcqOId_E80
Westlands Penthouse - $5000
View: https://www.youtube.com/watch?v=_3RRtMJjf_Y