Hi,
I live and work in this market in Dubai and I would agree that the best way to rent a property quickly is to use a reputable agency. They will advertise your property on various platforms (Dubizzle, propertyfinder, justrentals etc) and will do a lot of the work for you. That is their job! I would only use 1 or 2 brokers though as things can get messy otherwise with agents fighting over keys etc!
In Dubai, it is the tenant who pays the commissions (5%) rather than the landlord. Many companies also offer property management to take care of all the tenancy issues/renewals, maintenance issues, banking etc. This is particularly useful if you are an overseas owner. Most will charge 5-7% per annum for property management.
I would also be aware that the current law states that in order to evict a tenant, a landlord must give 12 months' notice to the tenant (served officially by Notary or registered post) and there are only a few reasons for being able to do so. The main ones are (1) selling the property (2) personal use (3) major repairs. You can also only increase the rental amount each year as determined by RERA's rental calculator, not whatever you wish.
The 12 months' notice can only be issued after the first year as well so the minimum rental is in effect a 2 year period. Many owners were prev kicking tenants out to get higher rental returns so RERA have stopped this by introducing the above. It is not wise to give some one notice on the pretence to sell or move in as you can be penalised heavily if you do not sell or move in.
I hope this info helps. Happy to recommend some good agents if need be.