Q: Water Leak

I have 2 refill completely or top off water (antifreeze) in plastic reservoir container right before I start up my car 2 go . somewhere. (Haven't driven my car since beginning Nov due to hospital so all this happened starting in summer months) I will drive my car, heater works fine, I don't have a temp gage so I don"t really know if car is running hot although @ times (not always) I can kind of smell that it is hot. When I park car & go back 2 it I happen 2 notice that water/antifreeze has leaked out from some-where. I have had my car about 2 yrs now but haven't really driven it much due to illnesses & hospital. The first yr I drove it maybe 2,000 miles & last yr perhaps a little more. I do have an extended warranty but it doesn't cover everything. When I took the car 2 a mini dealership 2 have oil changed they said was theromstat & needed 2 b replaced. I DONT TRUST THEM They didn't even test drive & at first said it was radiator housing but on paper put thermost & cost.

My car has 87000 miles.
My car has an automatic transmission. I wrote u a while back but can't remember how precise I was in asking question. I'm afraid of the $ cost just to find out what is actually wrong w/it & then more $ to fix it. I probably should have looked into the car's possible problems b4 I purchased it or bought more of a warranty which I did think I had purchased because I thouht of all possibilities re engine, but I do luv my car & am pretty much stuck w/it now.