social media accounts and monitoring tools

Dear Experts:

We are into real estate business we buy land constuct and sell the flats and apartments,

1.we are planning to create social media accounts , facebook , twiter and linkedin and google plus for every project as of now totally we have 10 projects hence on every microsite above socail media accounts 4 *10= 40 accounts.

Please suggest is this a good practice or this many will lead to more confusion , please help in the best recommended internet marketing practice.

2. If many social media accounts then we have to go for social media monitoring application one such i liked is Hubspot but will this allow multiple twitter accounts , multiple facebook accounts or reserved one account please suggest.

3. Is it possible to create social media accounts with our domain name or it requires gmail, yahoo accounts only. I think linkedin willl allow but can you please suggest with other social media accounts is this possible.