Withdrawing an offer but still interested

[RaSheila Smith]

Hi, I've placed an offer on a property I'm VERY INTERESTED IN due to the phenomenal ARV. The listing agent had over 30 photos of the property and I drove by to look at the exterior a few times. When I spoke with the agent, she said an offer had come in and I told her I planned on submitting an offer as well. I submitted a very competitive offer just $2000 less than the asking price of $200K. She responded that the owner would prefer I see the house before responding to my offer . The home was pretty much what I expected from the photos with a lot of character except that there is MOLD in the attic and basement ( unfinished ) which the agent disclosed immediately and why they wanted me to view the house . Mold smell throughout and owner supposedly has an estimate for remediation around $8K. They are ok with me reducing offer to compensate for mold remediation and owner also asking for 6-8 week closing due to buying another house. Question is, am I required to formally withdraw my current offer in writing or is my text to her that I will provide an amended offer after receiving their mold estimate the owner obtained sufficient . Also, anyone have a wholesaler friendly purchase agreement that says something like closing cannot be barred due to seller' delay or failure to purchase a home . Thanks in advance for the input