Build a Website

I would like to design a content management system for a real estate agency that is fully can be customized on an individual basis. Main points I would like are as follows - 1. Property Address 2. Owners Name / Telephone / Email / Address etc 3. Notes 4. Follow Up Calendar and alerts 5. Store photos 6. Insert property text 7. Residential / Commercial Property 8. Custom Filters - Suburb / State - Size 9. Bulk Email Sending 10. Email direct from site / Connect with Gmail / Outlook. 11. Custom Templates I would like to be able to sell subscriptions to my service in the future so would like this capability ready. I would also like to be able to give other people access to this with their own private login and there own individual database.