- What is the soil condition, and will it require any special treatment to be suitable for building?

The first thing to know about crowd funding solutions is that many are structured in a way that they would not qualify for 1031 Exchange treatment (e.g.,  membership interests in a limited liability company that are treated as partnership interests).  

I've landed an off market deal but I'm afraid I may be stretching some ethical boundaries.

There is some chance tenants will not know their rights under rent control, but I would not rely on this and I am not sure it is ethical to take advantage of their ignorance (I know the tenant advocates would say this is not right).  

@Daniel Overby Ozone treatment for sure.

Or some other form of treatment?

This is the snippet from the Massachusetts standard Purchase and Sale agreement that outlines the treatment at a high level.

Is it ethical for my Realtor to ask me what the rate quote was that I received from my loan officer, and share it with her preferred lender, who is also preparing a quote for me? 

I'd pay the first round of treatments, while informing them (and have in lease) that they will be responsible for future costs of pests as motivation to keep the place clean.

These are professionals with additional training and a stricter code of ethics.