Do I take it over with a lease amendment that replaces the property manager's name with our name on the existing lease?

If you are coming to the end of the time limit, then you should amend the contract to give yourself more time to complete the inspections. 

I think they could amend the original agreement to say agent sell X shares equally 60% ownership to investors A, B and C.

If you didn't report the income from the past years but you think that you should have, I would reach out to a tax professional to exam your previous tax returns and see if amendments are needed.

This can be handled by a lease amendment.

It's part art and science toe valuate shopping centers and what you can and can't charge for is all about the individual tenant lease.Often a center over time can have different attorneys working for both the landlords and the tenants working on new leases and or amendments.

Luckily I amended our contract agreement 2 months prior because although they were charging me only 7%, they charged a 3% surcharge every 3 months on all work related to the house--not including the 25% markup (WHO DOES THIS??).  

Documented it with LLC Amendment Form and signed it. 

This is an amended guideline which I wasn’t aware of when I purchased the property.

There is also an amended date of extension again with no sales price.