How many weeks' holiday a year are there? <a href=" http://www.sightline.co.uk/ventolin-over-the-counter-uk.pdf ">ventolin over the counter uk asda</a> If there’s a secret to Tesla’s success, it’s been to outsource as little as possible. The company has insisted on doing just about everything it can in-house, which has helped it develop intellectual property and control costs. Tesla built the battery pack replacement feature into the Model S, for example, and then designed the robots that will do the work.