Whilst my stay in Boosaso, we rented a 5 bed house/mansion, and all the other houses opposite where all owned by wealthy pirates and rented out by them. All mansions, where in the best shape, refurbished and clean. My mum would sometimes give me 100 Dollars to transfer to Somali Shillings, it transferred to millions and I had to take it back home in a shopping bag. As the currency of Somalia is not worth much, everything bought with high value i.e. lands, houses businesses are in Dollars. You'll definitely pay in Dollars if you consider buying a House or Land.
Building is nothing, if you secure a land big enough. My grandmother recently sold a 3 bed house, right next to the Boosaso coast at around $20,000. I was young and could not remember exactly how big the house was, but it was ruffly 20 meters by 20 meters (20 x 20) 4000 sq ft. Considering that house was near the coast/beach, and us Somali's love the beach, that house we sold has potential of becoming a hotel or a restaurant. If you look more inland Boosaso the prices are still similar, we own another house right where Boosaso ends (southward) towards Garoowe side, and that area is scary, dangerous AF. Walhi it was so quiet, no children, and the worst part is apparently the human organ smugglers operate from their. But that house we have in that isolated area is also worth $25,000.
So it depends what you want, compared to other cities in Somalia I went to, Boosaso was by far the safest, no crime, and a chilled environment. But I would recommended you secure a big land next to the coast, port area. You never know, when the Oil, Natural Gas are exploited, the economy will plunge up, and all houses could be worth double if not triple. I hope that answers your Question.