Custom work for Jomres v6 / joomla1 .7

Hello, I need a custom plugin or module that showld help me to insert in jomres 1000+ properties at once, using an excel/csv or whatever solution you can recomend. What can I do in order to have this plugin? I have the latest version of jomres(6.0) using joomla 1.7. The plugin should be able to work properly with future uptakes from jomla or jomres or at least to be able to easy-fix-it for new updates! At the moment there is no plugin (in jomress plugin manager) to import properties like this, only a way using API,but i think is a good idea ti create a plugin (most probably import them from a csv file). It will be a button in the admin cpanel whcih will allow us to upload a csv file that will be imported in the db. The idea is simple enough, building maybe it is more complicated. However, this csv file must be up to us to create (or the script that exports our properties to csv from our old db). You have to just develop a plugin that imports the csv to the jomres database. We need to know your standard rate for development /hour and to tell us how hours of work it will take. I need a quick answer from you if possible. Best regards.