The only real contract executed was the actual lease which does not allow pets.My change of heart lies in: 1.) their reveal that they won't be staying 2.) so little time left in their lease anyway (they have 8 months left). 3.) deeper thought about not knowing the breed, size, age, or being able to meet the dog.4.) new revelations about insurance policies5.) deeper thought about what this means for the other tenant of 2 years who may renew. 

I'm assuming you have someone onsite/staff to haul and place them as well. 

If so, and there is an approved variance, then get a copy of the staff report and a copy of the Resolution that the Planning Commission or Zoning Administor approved and signed to look for any Conditions of Approval that affect the site.

Did he show you any executed lease contracts, regular deposits or something proving the $450 rent history?

It will take some planning, diligence, and patience but it should be possible to execute something like this.

I have a company in Central NJ and we just charge a flat fee without any markups, or additional fees, but that might change in the future as we grow and need to hire more staff. 

Is it feasible to outsource the whole operation, including staff, and still earning on the business side?

To successfully operate parks at scale requires understanding all the unique aspects, having the experience necessary to create a strategy that works, and building a team and processes to execute. 

When you're buying of selling on a LO, there is no Down Payment since you're not buying the property until you execute the Option Agreement. 

Their value play strategy has been executed.