After you make an offer and give an earnest money check, you begin the inspection period (unless you waive inspection). This is typically 7-11 days and is stated in the offer. If you don't respond within that period it is assumed that the inspection is accepted. It's on the buyer to schedule the inspection(s) and respond to the buyer when completed. The buyer must allow access to the home, but typically can refuse to allow inspectors on the roof for liability reasons.
After the buyer receives the inspection report(s) - plural as you could call in several inspectors (for example a pool expert). You respond to the sellers with either acceptance, cancellation of the contract, or a counter-offer asking for concessions based on the inspection(s).
At the same time, in parallel, you would have informed the mortgage broker that you made an offer and they would start their process. They may go ahead and schedule the appraisal and it may occur before the inspection period ends. This happened to us. We put a bid on a house, and it was appraised before the inspection was completed. We ended up cancelling the contract and were out $450 for the inspection fee.