Hi Jeff, it may comfort you to know that I am a rehabber whom has acquired homes with mold damage. The remediation process is detailed and requires a specialist. However, if not done correctly, could pose a threat to your family.

Please be careful when looking at houses. Husband saw one 2 weeks ago and took pictures of the moldy basement. A week later, the basement had been freshly painted. I don't think they had even tried to "clean the mold off" as you could see places where it was still dark under the paint. We took more pics and found areas that were still covered in mold and unpainted. 

I think the house is out of the running but I would definitely have my inspector pay particular attention to those areas if an offer was made. Bank promised remediation and painting does no equal remediation in my mind. Make sure your inspector checks for moisture levels in walls! (To me, you need to do what they did in NOLA - you pull off drywall, treat and/or replace studs and put up new insulation & drywall as needed to make sure you are clean and safe!)

It depends on what is causing the mold also. A lot of bank owned homes have been sitting vacant for 1 year or more, and when a house goes through an entire year (especially with Maryland weather) with no temperature control, the house will sweat. This will cause mold. It doesn't always mean that there is water leaking through the walls.

I actually bought a home with a similar problem. I had a mold removal specialist come in and tell me honestly to just pull the drywall out, replace anything behind that looked like it might be damaged and rip the flooring out. We did and there wasn't a speck of mold anywhere behind the drywall. So the total renovation cost us about 1500$ and 2 weeks of time. It was worth it. I also had the mold removal specialist come out during and after the process. Luckily he was nice and for a small fee didn't mind coming out to check on the progress.

I think a lot of mold problems need to be evaluated on a case by case basis. There are a lot of deals to be had right now. Good luck!