Web Design - Google Maps overlay of information concerning public buildings

General information for the website: Google Maps mashup
Num. of web pages/modules: 10+
Description of requirements/features: This project is to display more information on with historic and public buildings in Northern Ireland. I wish to be able to click on a map (places in Northern Ireland - with the default being an area in Belfast) - and then click on certain buildings which have 'icons' which highlight further information. When a user clicks on this - it might simply show a nice summary box - stating name of building and what the plans are for that public space etc (it really doesn't matter to you - it is just text. However, we do need the feature also to provide or upload other media such as pdfs and/or images will provide further information on that building and are somehow contained or clickable from the same icon.

I wish to give users the ability to click on a building, place a 'flag' or 'icon' and then add their text, or images or pdfs to that building. In other words, they must be able to add material to the site so that the Google maps project website can be expanded over time by users where they can add more information on any building they choose.

Basically, I need a web based system where you log in and you see a Google maps view of an area in Belfast. That may change a little but for now they are speaking about the Georges Street area. I believe the co-ordinates are @54.6005548,-5.9277703,453 but it doesn't really matter. It could be any city from your coding viewpoint.

I would also like a login system. They ideally should allow a user to register an email or login with Google Plus, Twitter or Facebook.

I would like a saved places feature as well. Basically be able to zoom to different areas and click save and store this in a basic list in some manner so a user can retrieve their 'favourite' locations (or saved locations) later.

So to recap, I need you should be able to overlay some type of writing or symbol which gives a brief description of all (or some) buildings in that area (we can find the real names later) so you can see what each residential building is. They are interested in the public buildings (not residential). So we also need a feature where you click on particular buildings for which we have more information (they will give this to us, so that when we click on it, an image or pdf is opened). I need a way for users to upload the information on each building - so they need to be able to place a marker on a building, add a short description and then add some documents like images or pdf's as well to that marker. Finally, I need a feature to login to the site along with saved locations as well.
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