why don’t you get a landline number on your cell, there are plans out there that would do it, alternatively if you are not available to answer calls you can have a voice automated system set up. it may be cheaper than hiring someone in the long-run. lastly you may opt to have your landline transfer the calls to your cellphone…depending on pricing, with this one though..lol.
transfering calls can result in a hefty sum on your bill at the end of the month…So check it out with your provider prior to any decision as such.
Good luck!