2005 Dodge Caravan Heater Core

I took my van in to have the calibers replaced last week. When I picked it up the van was bouncing all over the road really bad. So I took it back and they told me I had a bad tire, (why they did not tell me this before, I have no idea). So I had them replace 2 tires and do a alignment as well. So then I pick it up last night and it was doing great till I got home and found water on the floor board on the passanger side front seat. I though well maybe I spilled my water and did not realize it. I dried it out and drove my kids to baseball practice. When I got home it was wet again. I got a white towel to see what color it was because there was no smell. It is clear water. What does this sound like to you? The car repair is telling me it is the heater core, but there is no smell of antifreeze and it just started when they did all this work. Help please, I feel these people are ripping me off!!!!!