Renting a pasture?

We are looking at a house that is about 8 acres and about 4-5 of it is a cow pasture. When we went to look at the house there was 3 cows in it and from satellite pictures I've seen as much as 10 cows at a time. It appears that neighboring farms have left the gates in between the properties open and the cows kinda come and go. It also has a very slow moving stream that runs through it. I was wondering if we decide to move to the house and not get cows ourselves what would be reasonable to allow them to have their cows in our pasture as well? Whats the going rate how does that work? For allowing them to use the pasture we get a cow in return processed or we get hay? Anyone have experience in something like this? We are looking to get chickens and pigs, but the cows are up in the air. We don't need that space and I wouldn't mind being friendly with the neighbors and cows as long as they help with upkeep since they are using it.

Some of the satellite pictures you can see where he regularly drove from one property to the others through the gates. When we went to look at the house he used the driveway which is a shared driveway between the houses. The neighbor owns about 70-80 acres all around this property on different sides of the road.

Thanks for the input.