So I do not have nearly as much experience as most of the active members on this site however I have heard enough knowledge to regurgitate what I have been taught. Best practice is this: Do your initial walk through with the seller, get them to sign the contract and find your buyer. Once you do this inform your buyer that you have located your cash investor and schedule a time in which you both can view the property. Keep in mind that in this scenario you are either "fixing and flipping" or "wholetailing" or "buy and holding" and that you require a cash investor "lender" to facilitate the means in which you are going to buy the property.
Yes unless you can schedule them back to back or if it has a lock box on the property. Both agents will also need to complete and agent visual inspection.