Buying a house with mold in the bathroom

[Alex Silang]

I've spent an hour doing internet research. Apparently mold health issues are exaggerated and removal services are oversold and often a ripoff. But I still do not know what to do. 

I am inspecting a possible purchase. The inspector found what seemed to be mold in the first floor bathroom. There was a leak previously, which supposedly was fixed. 

Seller's agent a few days later said that it wasn't mold - that "something" spilled in the bathroom. I find this hard to believe, because it's head level and its on opposite sides of the bathroom. Inspector suggested it might have been even painted over. 

My real estate agent is taking his word at face value. According to her, there is no issue. "He seems to be trustworthy"  "It would only cost $1,000 to take care of it, if it was a problem"

What would you do in my shoes? I was looking at test kits from home depot. Very affordable, but it can take 3 weeks to get results.