[Typo3] I think I'm in over my head

[Jamie Evans]

Hello,

I started working on a CMS project for a real estate investment  
company.  They want a website where clients can login and view  
properties their invested or interested in.  They also want their  
employees to be able to login and manage those properties.  I decided  
to go with typo because of the permissions issue...It seems to me  
that typo is the only opensource framework (although I could be  
wrong) that allows client a and client b to view the same property  
while client c views another property.  I thought this would be  
straight forward, but the more I research, the larger this project is  
becoming.  There is a potential of a couple hundred managers and just  
as many clients.  Also I guess there are hundreds of properties in  
the database.  Does anyone know roughly how long it would take one  
person to develop a site like this?  Please feel free to throw out  
some numbers as to how much this would cost to hire a company to do  
this.  I've never done a project on this scale and I have no idea  
what it takes to accomplish this.  I know this isn't a typical  
question for the list, but I'm really stuck here and any advice would  
be greatly appreciated.  If anyone wants to take this conversation  
off the list my email is jamie at pueomedia.com.  Thank you very much in  
advance for the help!

Sincerely,

.:.  jamie