A Shrine in the Parking Lot?

There's a 5-car parking lot in front of the English language school I work at. Only 2 of the spaces seem to be in use, so I wish they would lease out the others, but whoever owns the parking long claims them to be taken. Hmm.

On this small piece of land, there's this tiny shrine, complete with the red posts/gates leading to it. Not only that, but the Ojizou house that I posted before, also is on this same property. So I ask, why, is there a small temple for the buddhas and also a shrine on such a limited amount of land?

This part of town is definitely not considered a tourist spot, so why? Why both a temple AND shrine?

The difference between a temple and shrine, from what I've noticed are these:

-temples: They have buddhas.

-shrines: No buddhas. They always have red posts/gatesleading to the shrine.

I don't know if this is true or not, but a taxi driver in Kyoto who was also acting as a guide, said that shrines worship birds as gods, and so the gates were placed for the purpose of giving the "gods" a place to rest. Makes sense, but is it true? I wonder if the number of posts have any significance?
A majority of Japanese people aren't religious, except on certain ceremonial events such as weddings, funerals, and certain national holidays. As a result, they go to both temples and shrines and seem to have a polytheisic belief.

Someone is taking good care of the Ojizou and the shrine in the parking lot. Who is it? What are these used for? The mystery of my surroundings keep growing.