Trying outside mechanic there are few prerequisite bro. Mechanic/workshop should be trustworthy, they should be professional, they should be reasonably priced. And to find this, im afraid you have to try few and find one. As person very good with me, might bite you in some cases (IMHO). There are few good garage in umm ramol, rashidiya and al quoz. What i suggest is drive to either/all location and just meet the workshop and see how they talk, respond and sound (greedy/professional) and then try once. I myself do this, when in need of new / specialize place. Or else, you can go to bigger places like Max garage, Technical garage, Dynatrade where everything is 1 dh lesser than Habtoor and very professional and trustworthy.