Nanny 1
Pros:
very experienced
knows the area
glowing references
Cons:
quite expensive (not sure what you mean by this, as it is you who decides the salary not the nanny. Is it that she may not take the job at the salary you are offering, in which case they are not in the running.)
not flexible on days (an employee wanting fixed working days/hours is not unusual)
Nanny 2
Pros:
seems very sweet and warm
was a nurse in her country
has two children
more reasonably priced (see above, it is you as employer who dictates the salary. What you mean I guess is that she will accept a lower salary)
keen to help with housework (though would she be able to do that as well as care for your children. Nannies are expected to do some light housework, so Nanny1 would be doing some).
Cons:
niece of my current babysitter (I see this as a negative, as it may mean you feel you have to employ her because you know their aunt. Their aunt may also may get involved if there is ever a disagreement between you)
just arrived in the country
doesn't know the area
a little shy (so am I at first)
question over how she will cope with oldest child.
has two children she has left behind (how old are the children? Will she cope being away from them?)
her Aunt will be very upset if I don't give her the job (see above, would aunt get too involved?)
Are either of these nannies actually in the running? Is Nanny1 is wanting more money than you are offering? If so, they are not in the running - you can't afford to pay them what they want and if you did hire them on less money, then they might leave for a better job after a short time.
Nanny2 has just arrived in the country... will they stay long, will they miss home especially as their children are there (their children may be in their 20's or they might be young... do you know how old they are?).
For both nannies - are they legally entitled to work in the country? It's something you need to check before hiring someone. Do their references check out ok, do they seem fairly healthy (always hard to know but sickness record with past employers may be an indicator).
Is it live-in or live-out. If live-in, you will need to decide if they are someone you can share your house with. With live-out, you need to get on with them but don't have to put up with them for quite so long each day as you would if they lived with you.
Neither to me seems totally ideal. Any other candidates?