Car rental recommendations for visitor?

[Anonymous]

My mother-in-law will be visiting with the family for about two months. Since we have only one car, and she would like one of her own (she'll be helping with before and after-school care), we would like to know of some inexpensive alternatives to the traditional, expensive Car Rental (e.g. Enterprise) options. The car rental would be for 2 months and short distances, around the neighborhood driving. Any recommendations???