He did provide a message with an insert that says if interest is transferred or sold without lenders prior consent that they would give us 15 days to pay the loan in full.

I can provide a consent and confidentiality form in order to protect your identity.

I used a RE attorney to have the home deeded to me and had a letter of consent signed by both myself and the seller  and sent that to their mortgage provider.

Sold the rental in avondale early last year when I realised I could get a council exemption to get subdivision consent and seriously increase the value of the property.

Something like:  During the period from the date of execution of this agreement through and iuncluding the closing, Owner shall not enter into any leases or extend any leases covering any part of the Property without the written consent of Buyer.

Nothing can happen without their consent and approval and, would require a hearing.

Said disbursement instrux cannot be modified without the expressed written consent of both buyer and seller. 

The seller is firm on the price (because seller's market and all the jazz, shark fest out there) and the house is already occupied by a renter so we can't just kick them out to do lead testing and fixing, even if we consented to pay for it out of pocket, without any extra negotiation.If we go through, we are afraid we are exposing ourselves for liability.My husband thinks this is OK - but I am chicken.Am I overreacting?

If the tenant is not communicating with you, that falls under the "tenant unreasonably withholds consent" clause and you can post a notice on the door at least 12 hours in advance. 

My contracts allow me to provide materials with contractors consent.