Looking for a reasonably good but not expense wireless camera system

[#Michael]

So kind of a nanny cam or household wifi camera system.  Basically, I live up in the north burb's of Chicago and will traveling into the city now everyday for work.  That means a train ride.  So, one of the neighborhood kids is going to walk my dog for me when he gets home from school.  And while he is a good kid and trustworthy, let's be honest, we live in an interesting world.  So, I want a couple of wireless cameras to keep an eye on the place.

 

I really don't need full hd cameras.  I was looking at the nest camera system and it looks good but for 3 cameras it seems very expensive.  What other systems should I be looking at?