Virtual phone numbers?

hi there

I need some advise please from all you clever computer people, I have a small business, I currently have a landline phone a personal cell number that clients text me for appointments.

im going to take on timely booking system and need to cut costs, I was suggested by a friend in the same business that has a virtual phone number to get one.

so im going to get my landline disconnected and put eftpos on wifi as Im with kiwibank and they don't have the new eftpos key you can plug into your cell phone to convert it to a eftpos unit I have to stay at the moment with eftpos terminal as I don't want to change banks as I just have again !!!

so im going to go wifi in the mean time and get rid of landline but don't know who to go with as I've googled virtual numbers and some say free but sounds dodgy.

any help or advise would be appreciated as im getting alittle frazzled

so in time I want to be eftpos terminal free, landline phone fee,.

thanks