Egistos is in a fantastic location, an area just outside of Pisa called Riglione. Its easy to get to (the bus terminus is to the left of Pisa Centrale train station and you take any bus which stops at the first stand - i.e Pontedera or Cascina buses). Nearby there is a Spar supermarket, a laundrette, several places to eat, shops for clothes, toiletries, toys and also some bars/community facilities ('Circolo Arci Pisanello' on the main road and also 'Bar Gala' along the street from Egistos are friendly inexpensive places to eat/drink). There are also several park/play areas for children nearby.
Transport links are by bus into Pisa or surrounding areas, but there is space opposite Egistos for a car to be parked if required.
Egistos itself is a large building containing 10 self-catering apartments. The rooms are very basic but relatively clean and generally contain two single beds plus a sofa bed in each, in addition to cooking and storage facilities. Room 7 has a private veranda and the rooms at the rear of the property have lovely views over the river Arno and surrounding countryside (there is a walkway along the banks of the river which is easily accessible from Egistos). Some rooms have an air conditioning unit (which will cost you extra) and heaters although it can be difficult to regulate the temperature in the apartments (we visited in August this year and had to run the air-con pretty much all of the time to keep the temperature down but have stayed on other occasions in the winter and found the apartment to be difficult to heat properly).
The average price is around 50 euros a night, but this seems to be the cheapest rate that we have found in the area so far.