Hello, I am a solicitor with 20 years experience. I will try to help you with this.
For about £8 you can get a copy of your Title Deeds as registered at HM Land Registry. You can also obtain a copy of anyone else's Title Deeds for the same amount if they are registered.
All you need to do is to click on www.landreg.gov.uk and click on the English or Welsh sections. Once in click on "information about finding out about property ownership " and follow the instructions. No-one will know that you have obtained a copy of their Title.
Remember the boundaries shown on the Plan are only a general indication of the boundaries.If you do not know your Title Number or that of the property you wish to look at do a Public Index Map search and you will be given the Number or told that it is not registered.
If you see "T marks" on the plan, then these point in the direction of the owner who has to maintain the wall, fence or hedge. (See the diagram below.)
'H' marks indicate a party wall: