We haven't completed yet, but I've never heard of an "urbanistic charge" issue? What is it?!
I've only heard negative things about Martin Cowling and Costa Furnishings. I think there are much better options if you want a package, eg Imperial, RNA Home Decor, Galeria (on the N340), Interior Sun gets a lot of positive comments - have a look at the General Forums under the "Furnishing your property" section. At this time of year and depending on what you want, you need to bear in mind that almost all factories in Spain close for all of August, so if you need to order things and want them before August, it needs to be done now! there's an Ikea in Seville and one due to open later this year in Malaga.