If you have access to the PoA document you should have it reviewed by a local attorney to determine when it takes effect. Many powers of attorney are springing, in that they only take effect once someone has been declared incompetent or incapacitated. Additionally, if you determine that it would be in your father's best interest to alter the type or scope of the power of attorney you should do this before he becomes incapacitated as it is likely that he is currently able to make changes.
Many courts have self-help clinics or clinics for low income clients. Try contacting a nearby courthouse to see if someone is available to assist with document preparation. You can also try calling the NV State Bar for a legal aid recommendation.
This question is difficult to answer without more information about the specific provisions of the contract. It seems from what you have said that they would be acting within the parameters of the contract to withdraw at least $500 for early termination but you should probably have a local attorney review the rest of the contract to determine what grounds the company had for charging you for the service and shipping.
If your contact with the other party has been classified as harassment then you should probably stop any further content with them directly. If they are being represented by a lawyer you should deal with the lawyer from now on.
I find it unlikely that defamatory statements would be taken to the police but if this person is going to seek legal action you will need an attorney to respond properly.
Your lawyer will want to see copies of all contact with the other party as well as anything...
The clause you're quoting is called a "merger clause" and states that as to the subject matter of the contract, that agreement will take precedence over other agreements between the same parties. You will probably want a local attorney to review all the relevant documents to determine exactly what is being superseded but generally that agreement between the school and your wife would only trump other agreements for the same subject matter between the school and your wife.
While I do not practice in your state, I believe that MN has moved away from requiring independent consideration to enforce a non-compete but that is only in the employment context. Your biggest hurdle will be that you signed the agreement and agreed to its terms when you could have taken one look at the non-compete clause and found another school. Courts will look at the facts of every case when determining a non-compete clause and consider such things as the reasonableness of the restriction(...