But I also need help with some clean up, I have a non performing self storage facility.  

If you're lucky you might find a GC to just hire you for what you can do, they might let you clean up, paint, lay sod, or general labor....you won't save that much but maybe some.

I could understand a serious cleanup if there was a foot of sewage in the basement.  

The only way to know for sure is to get it so considering the amount of your purchase and the potential cleanup costs if there is an issue, perhaps it is money well spent.

The most common kind of deed other than warranty is quit claim, in which the grantor is transferring title with no warranty of his ownership.Don't get too hooked up on previous title transferred as the use of title insurance in your purchase will move the risk of good title to the title insurer with the result that the insurer will likely clean up any title issues prior to issuing a policy.In most jurisdictions vendor lien means that a reference to a mortgage or deed of trust is made in the actual warranty deed.  

It just sits there and gets progressively more and more overgrown with the risk of falling into disrepair.As I have little investable cash right now to buy such assets outright, I would like to approach owners of such buildings to negotiate and agree to let at a discount rate that reflects the current state of the property, pay for the cleanup & marketing and then sublet at a profit to a Third Party when the building looks tidy again.

These were intended to clean up daily at your personal house in perfect conditions.

We would like to completely renovate the kitchen, paint and clean up the bedrooms, refinish all the floors and add a shower stall to one of the bathrooms.

I've heard of situations like this that turned into $40k body removals with bio-hazard specialist cleanup crews involved. 

I have, and that much money for a flood cleanup is absolutely nuts.