Adding a new functionality to a profile

Hi All,

I am new to Elgg and is at a stage where im trying out different social network frameworks. My choice will depend a lot on the ability to add this feature which I will describe in a bit.

Basically im creating social network for an application im developing for my final year project. Im using a social network to manage the users for my application. 

The functionality i require is to enable the users(shop owners) add different items to their supplies list and the capability to manage them through their own administration.

So my question is, does Elgg allow us to do this? if yes, on what should i look at, as in, is it a plugin? or should I start coding from scratch? or is it something else?

It would be great if some one could clear this up for me asap.. :)

Thanks and Regards,

Dhanushka

P.S. so far i think Elgg is the best :P