The real estate is going down everywhere, including in Qatar. Of course the official media (newspapers, real estate agencies, etc.) will not tell you so, or they will minimize the extent of the downturn. The real estate will eventually go up again, but it will take time. I estimate that prices will go down in Qatar for another 3 to 5 years, and will slowly pick up thereafter. If I were you, I would post-pone my purchase in Pearl by at least 2 years. In the meantime, you can rent an apartment in Pearl to ensure you really like the place and the maintenance is within your budget. I notice that vitually nobody considers the cost of the maintenance. But unfortunately maintaining the building (including extraordinary maintenance) takes a budget on its own. And considering the poor materials and poor construction practices utilized by the building Companies in the Pearl Qatar, I strongly reccommend that you take the cost of the maintenance into account.
Best Regards.