I have actually done some work on this and VETTED a few company´s
What´s amazing was how many people I found that had no idea where the resort was and that were nit operating legally in Spain
One of the most important things is to take references and ensure that they are a legally registered business in Spain because if they are not it can effect your insurance
I do not think that it is fair to publish their details on the forum as it will result in a barriage of people also saying that they are offer this service but if you PM me your e-mail address I will send you their brochure