Private CN or Agency

Hi everyone, I've been on a lookout for CN and can't seem to decide on one. The private hire CN seems to be more experienced and at least I talked to her before, but I am worried as my pregnancy is considered high risk and I'm not sure if she'd be available if I were to deliver earlier.. that being said I'm also unsure of insurance and levy costs...private nanny need to pay for these? I only know abt these things from quotation from agency... currently considering CA or PEM... any thoughts or suggestions will be appreciated... thank you...