Have apartments use mifare 4K fobs. Common area can only access bike room 1 would be possible to use flipper to get access to bike room 2 ? Using data from fob that can access room 1?
Here is the general Mifare explanation but I’m not so sure everything applies to Mifare 4K. I believe 4K is reverse compatible. Some of the keys(particularly to common ares) may be Mifare classic compatible. Have a look at this and please let me know if it helps.
What you’re talking about is not controlled by the data on your card. Your “access level” is determined by the access control system. All that is store on the card is a unique ID.
John Smith has card number 123. John smith has his access level (in the access control system) set as “bike room 1”. When card number 123 is identified at the bike room 1 reader, the access control system sees that card 123 is allowed into bike room 1, and unlocks the door.
If John Smith uses his card (number 123) on the bike room 2 reader, the access control system will identify card 123, and see that it is not allowed into bike room 2 and will not unlock the door.
The usual attack here is cloning the building managers card here not your own. So obviously you now want to advise the building manager to keep his cards in a nice radio-blocking wallet or similar.
Also, some older/simple/cheaper door access control systems just use sequential numbers for the ID so they are guessable, with either zero or one being the super-admin user. However your DAC will probably alert on an unexpected ID, so this isn’t a feature you want to play with without permission.