Honesty is best policy here....talk to customer openly and ask them what theybwould like tomdo under the circumstances......in all likelihood they may ask you forma referral to another GC or perhaps they will ask if you could stay involved in a lesser capacity that excludes site visitations but still managing project and numbers, etc.
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I agree with the previous poster. You need to have a frank conversation with your client advising that your health condition will not permit you to complete this job. I suspect that they would rather have this conversation with you before the project starts. Good luck.
DISCLAIMER: Please be advised that this post is not intended to constitute legal advice and is for informational purposes only. This posting in no way creates an attorney client relationship. You should contact an attorney to protect your interests.
The following needs to happen, you need to have a "heart to heart" conversation with your clients about what is taking place. As the previous attorney stated, "honesty is the best policy." Attempt to find a general contractor to replace you. In addition, once the replacement is working on the job site, you need to protect your interests, by obtaining releases from the other parties.
The information is for general information purposes only. Nothing from this comment should be taken as legal advice for any individual case or situation. This information does not create and does not constitute an attorney-client relationship or a prospective attorney relationship.