Need both UX/UI design and backend developers for new site/app

First, understand I am EXTREMELY cynical of web developers. I have been burned for too much time and money to count. You would gag. I've dealt with giant firms, and individuals, and in between. The industry is smoke and mirrors and fraught with cons and incompetence. I will require you to set the expectation, manage it professionally, and deliver as promised. I will not hand you an open checkbook. I will hold you accountable. You are NOT the ultimate gift to the world with your skills. Now, if you are still reading, I can be a great guy to work with, provided you are honest, transparent, and conduct yourself with integrity. I will provide a scope document and some example sites to help you understand concept and functionality. I am NOT going to tell you exactly what to do and how to do it. You are to be the professional who's expertise I am paying for. I will do all I can to communicate my vision... you make it a reality and make it work well, using your knowledge of customer behaviour on the web and mobile, etc. It is a niche market (distance motorcycling), subscription-based model. Users connect with one another, rate, share, etc. Dynamic mapping will be critical. Simply using Google maps is not likely to get the job done. Best case would be to find a team interested in being in this for the long haul, as the site will be forever evolving and growing. In my perfect world, someone in design or development will also ride a motorcycle, but I know that is very hard to find, as us riders generally don't enjoy technology or interacting with it. The site needs to be clean, very professional (not cartoony), and VERY easy to use by people who don't get their kicks screwing around on computers and tablets and smart phones. If it gets fiddly or difficult to use in any way, the target market will drop it in a heartbeat. Mapping, database building and linking, and constant drawing in of user content and information are the key elements of the site.