Clear up-front communication is key. Most of the time there is a 10 day turnaround if the application is complete. More complex projects will take longer of course and that is communicated at application submittal.
I believe advertising a property "as is" just means the seller isn't willing to make repairs. It doesn't relieve them from permit or disclosure requirements.
There is a lot of remodel work that can be done without permits, and there is a lot of missing information in this thread, so it's hard to give good answers. Did the buyer use a Realtor? Have a home inspection? Do their due diligence (investigate history of property)? What specific issues are...
I can understand someone getting frustrated and/or impatient if the timeline for the review process is not communicated to them up front. Simply letting the applicant know the process can take 10-15 days would alleviate some of that. But I do not recommend moving forward without a permit. They...
It depends if the permit is still active. If it is expired (depending on how long) a fee can be charged to reopen, or a new permit application can be required by the Building Official.