[Web app] Classifieds/product search from XML feeds - PHP or ASP.Net

I need to build a searchable XML feed search/aggregator web application (Mainly product/classifieds feeds) in responsive web design. There should be an option to create categories, sub categories and fields in the system to which the xml feeds are matched. The application should be configurable to add different XML feeds with similar fields and map it to the local system fields. There should be an admin section to configure it and manage the feeds (like black listing certain entries from feeds). The main purpose of the site will be create product search engines, price comparison websites and classifieds search aggregators. The site will help users to search from different sites which provides their contents in the form of XML feeds. This configurable script should be useful to create search/aggregator websites in different niches. For eg. products like mobiles, electronic gadgets, fashion, health and beauty products etc... and classifieds of different kinds, eg. jobs, automotive, real-estate etc.. It will be good if the site is SEO friendly. Please visit the following sites for better understanding: [login to view URL] [login to view URL] [login to view URL] (This one uses only eBay feeds. Our system should search from multiple feeds) The app can be either in .Net or PHP. I am an independent developer who is trying to build an innovative we app as a startup. So the budget is a big constraint. Using opensource (free) elements, frameworks and CMS as a backbone to reduce development cost will be highly appreciative. Apart from that, I would like to offer a full code ownership and copyrights to established developers or companies in exchange for a low quote. It will be a win-win situation as it is a product you can market or publish yourself. Only condition will be a non compete agreement on the use of code. Few questions: 1. Are you comfortable in web designing (preferably HTML5/CSS3. We need only a simple neat design. A provision to template and themes will be an add-on)? 2. How good you are at performance optimization? (your previous experience, understandings and challenges) 3. Preferred project management system and development life cycle? 4. How much time you normally allocate for testing phase (% of total project timeline)? 5. How good you are at SEO? 6. What will be your normal working hours? (along with your current time zone) 7. Mode of contact? 8. Availability and rate for live product support and bug fixes (after release)? Feel free to contact me if you need any clarification.