Just yesterday it seems, a prospective home purchaser and their real estate agent would plan a few hours or a day of home shopping - visiting the various houses on the market for sale - and the buyer and their agent could casually discuss the pluses and minuses of the home they were in, financing options that were available to the buyer, strategize about making an offer etc. - ALL WHILE PRESENT IN THE HOME!
Welcome to the New Millennium! Cameras and microphones are EVERYWHERE and it would be wise to be cautious about appearing and talking excited, desperate, or even insulting, while physically inside a sellers home which you are considering and may decide to make an offer.
More often than not, home owners (sellers) have installed in their homes, security devices to protect against unwanted intrusions and burglars, or simply a "nanny cam" to keep an eye on the baby! It is becoming less expensive to afford multiple recording devices, and even to have events streamed live onto a smartphone. This is a GREAT Benefit to have in aiding police to capture a criminal who is terrorizing a neighborhood, but could also be a Great DETRIMENT to your wallet and your negotiating position should you unconsciously "spill the beans" about how badly you want this home!
It is a good idea for both you and your agent to have a plan about how to behave, and what topics of discussion should be off the table while inside your prospective new home. Consider taking notes for discussion AFTER going outside, or back at the real estate office.
As the saying goes:
Loose Lips Sink Ships. Be careful not to sink your own ship before it even sets sail!