Is This Mold?

Hard to tell from those photos. In #2, there does appear to be mold on the lower portion of the drywall on left. You can try spraying a mist of bleach and if it turns from green/black to an orange/tan color, that's a good indication.

Is this a property you're thinking of renting or buying?

Thank you for taking the time to respond and I will be sure to try that but no I've been renting this apartment for almost 3 years

OK. What's I'd advise is to thoroughly clean wherever you have indication or suspicion there is mold. Bleach kills it quickly. You might have to do some painting after but if so, wait a few days for the bleach to dry.

Any health problems over the three years?

Is that an air vent? It looks like it hasn't been vacuumed in a long time

Vacuum and then mist with diluted bleach. See what happens.

Yes there have been health issues, and the wall discoloration is on every wall, it appears that there is something coming through the paint rather than growing on top of it. I have actually tried to scrub it down with 409 but will not come completely off.

Very likely then the mold is deep, running through the sheet rock and in the wood behind. If every wall, you've got a serious problem. You really should find another place to rent and do so as quickly as you can. Is that possible for you?

No not at the moment nobody seems to believe me and my landlord told me that it's my fault and to take a toothbrush and bleach and scrub it clean.