Here is the complete text :
http://www.porlareserva.org.ar/Ley1166.htm
Not sure if you need a lawyer to do that.
If you are planning to sell ice-creams on a small scale that way -sorry to be Mr bad news- it is forbidden :
Venta Ambulante por cuenta propia
11.3.1 Pueden otorgarse permisos de uso para ejercer la actividad, en áreas y horarios determinados, únicamente para la venta de los artículos establecidos en 11.3.3.
11.3.2 Para obtener el permiso correspondiente, los/as postulantes deben contar con la correspondiente inscripción en el Registro de Postulantes para la venta en el Espacio Público.
11.3.3 Se autoriza la venta ambulante de los siguientes artículos: maní en su vaina, descascarado, tostado o sin tostar, castañas, garrapiñadas, manzanas abrillantadas, higos, azúcar hilada, pochoclo, barquillos, fruta desecada, descascarada, tostada y seca.
11.3.4 Queda expresamente prohibido el expendio de agua, bebidas sin alcohol, helados e infusiones, que se rigen por lo normado en el Capítulo 11.10.
If it's not ice-creams, it seems there are a few requisites :
- 2 years of continuous residence in the city of BA
- if you are otorgated a licence (valid for one year), you need to run the business by yourself
But I'll stop here since if you plan on selling ice creams, it is strictly forbidden if you want to do it like a small entrepreneur.
It can be allowed though on a larger scale (see points 11.10), but the norms are excessively strict (you would need to hire certain type of persons, you could only sell ice-creams coming from specific providers, times of selling, places forbidden and so on...)
EDIT : of course it's only my quick opinion based on a very quick reading, but more or less this is the panorama