Seller breach of contract - legal needed

[Erica Post]

I'm seeking a real estate lawyer (legal advice) who is able to write a letter (at minimum) on my behalf to a seller who is currently out of contract on a SFH in the Tukwila area (purchased off MLS through a licensed Realtor). Per the Purchase and Sale agreement, the home is contracted to close "on or before 3/24/17"; up until this evening we were on schedule to close in two days, on Tuesday, 3/14/17 at the seller's request for an early closing (e.g. all my pieces of the agreement are complete).

Two major issues:

1. 

Following inspection, we (buyer) filed a Form 34 detailing specific repairs to be completed by the seller, to which the seller agreed (seller was insistent upon contracting work and not providing credits). Fast forward to a hastily completed job that did not fully meet the requirements and caused additional problems/work for the buyer (me) to remediate, and a seller unable/unwilling to complete the agreed-upon work within the confines of the Purchase and Sale Agreement terms, or provide appropriate credits for outstanding work.

2.

The offer on this home was based on four major items being completed (we have in writing from listing broker): new roof, crawlspace insulation, attic insulation, french drain/sump pump. Seller then backed out of agreement for crawlspace insulation (which we elected at the time not to push), however the additional work of the french drain/sump pump does not meet Form 34 agreement.

At this point, the seller is offering a minimal credit (not enough to cover the outstanding work from the Form 34) and not addressing the issue of the crawlspace insulation originally agreed to in writing prior to the submission of the offer. The seller is instead threatening to "not close" unless I sign a statement saying that the "work was completed to my satisfaction", which it has not been, so I am not willing to waive that right, as I estimate the outstanding loss to me to be ~$4,000. My understanding is that the seller is requesting this statement as she is afraid of being sued following the completion of the transaction.

The listing agent has engaged in character defamation (in regards to me) when speaking to the contractors engaged to do the work as well as the seller, and has also flip-flopped on agreements for work to be completed, and also verbally said the seller would provide a $6,000 credit (which never materialized). Her ethics are questionable, and we have caught her lying on more than one occasion. The seller is out of state (FL), so all contractors and work have been hired and supervised by the listing agent. The listing agent has admitted on more than one occasion to having been responsible for a contractor miscommunication (which caused part of the fallout over the Form 34), and also admitted that an appliance (microwave) listed as included in the Purchase and Sale agreement was moved out with the tenants and is now missing.

If you are able to assist, please contact me as soon as possible. I will update this post once I have received what I need. Thank you.