assistant / va for property developer / lettings co ordinator and all round brilliant helpful person!

I am looking for someone to
Manage my lettings business as much as possible
Promote my property development business and project manage jobs.
I am looking for a dedicated person for the very long term to do most of the back office work. this person must be good with excel and able to project manage different jobs. Must have a lot of common sense and be intelligent.
Be there at all times, whenever is needed on the phone, email, and what's app.