Depending on the age of the house if asbestos or oil tank remediation has been done.

Is it worth trying to remediate that much mold?

I'll take a mold problem if I can purchase the property from 15k-20k, and rents are 850+ a month, and its only a few thousands cosmetic dollars above mold remediation that will fix the problem (~40k all in costs).

@Elizabeth ColegroveI do not have it in writing, but the exchange of texts suggests I am concerned about the tenant and looking to remedy ASAP. 

Since you already did the work to remedy both issues, the right thing to do, in my opinion, is to disclose these issues as well as all the work done to correct them and turn it into a positive.

Have a no smoking inside the unit policy, in your lease, and if it is violated you remediate with the deposit.

Are there any remediation concerns?  

Without the normal legal remedies available to our clients, our hands are tied and we are unable to do what's right for our property owners in some cases. 

The GC I will be working with will provide me the cert for the mold remediation.

How much is the house, how much will it sell for when it is all fixed up, how much mold,’what kind of mold, and on and on Personally I would call two mild remediation companies and ask for a quote from each