https://www.broadbandchecker.btwholesale.com/#/ADSL/AddressHome
This is probably a good place to start , look up the survey note for your address , this is for a fully ducted property,
Our records show the following FTTP network service information for these premises:-Single Dwelling Unit Residential UG Feed with no anticipated issues.
If your survey note is ‘partial DIG’ , a nearby jointbox will contain the CBT allocated for your address , and a new duct will be provided from that box to your house wall , however unless cars park on the footpath it shouldn’t be necessary for you to know which jointbox , if the survey note is ‘built to the curtilage’ a Toby box or duct marker should now exist but in the path outside your address ( so only your own garden to get across ) so again there shouldn’t really be access issues , and a scar in the footpath should lead you to the footway box containing the CBT .
If vehicles do park on the footpath, and that stops the jointbox with the CBT inside being accessible , then that’s is a job stopper ….however knowing which footway box it is impossible to know for sure
Openreach boxes depending on how old it is , could be marked as PO , BT or Openreach , the one serving you would be within 100m but probably much closer, it’s a case of looking for the closest one ( or closet ones if they exist either side of your property ) and if cars regularly park on them , asking for them to not do so , obviously the problem becomes predicting when access will be needed by OR or their contractors
