Hi,
I would suggest you to better specify the question in order to obtain a meaningfull answer. The question you have just posted is too open and nobody will be able to answer that without a better specification.
Time necessary to install a system is entirely dependent on the type of sensors you have and also the type of programing enviroment you choose. Also, the state of the existing system needs to be known.
I would suggest you to call National Instruments and talk to a Inside Sales Representative or even try to find out who is the NI Field Sales Engineer in your area for a possible visit...
Such an open question will probably not be answered in a discussion forum like this.
I hope it helps
Andre Oliveira