hotel reservation system for multiple hotels

software will be a reservation button on the hotel's page. when pressed it will take the user to reservation page . custumer will select dates and room type on the page. this page will show the price and availibility of rooms around the custumers chosed date. when custumer make selection it will go to the payment page on which the payement will be finished. hotels will have a web client which they use to check reservations and enter offline reservations . hotels may have more than one locations. in that case an admin account will have control over all the locations and local users will have local rights. software must be able to accept more client types (eg villa renting, recreational activities ) software must be able to acceptboth global online payment systems or clients own system. i have to be able to get detailed reports about clients and custumers going through system. i am not sure about the language it must be written. i prefer asp but open to discussion winning bid must be avilable after project end for paid maintenance around 15 hours a month.