Boundary agreement for self build

We are seeking guidance on the most appropriate method to record boundary positions for our property before completing a later Transfer of Part. We have: - Applied to amalgamate three adjoining freehold titles in our ownership (DY300342, DY382898, DY382907). -Prepared an informal boundary agreement with both neighbouring proprietors (DY421683 and DY382898) and drafted AP1 for each - to be submitted once amalgamated title is completed. - Measured and mapped the boundaries according to what exists on the ground (which differs from older deed plans). - Obtained written agreement from both neighbours, who are willing to sign the informal boundary agreement and associated plan (see attached drawing). We would appreciate clarification on: Will an informal boundary agreement, signed by all parties and supported by an accurate plan based on the physical features on site, be sufficient to note on the register to record the agreed boundary position? Is an informal agreement of this kind considered adequate for future reliance in the event of a dispute? Or, given that the historic deed measurements differ from what exists on the ground, would you recommend that we instead apply for a determined boundary? Is a determined boundary only necessary where an exact fixed legal line (to HMLR technical plan standards) is required or where a dispute exists. There is no dispute currently. We want to ensure we proceed in the most appropriate and proportionate way. Thank you for your assistance.

Andy &amp;amp; Rachel - we register the general boundaries only. A boundary agreement does not alter the registered extents so if the purpose of your agreement is to explain the position of the boundaries on the ground, but not alter any registered title, then that's fine. A determined boundary goes further with regards defining the boundary but again does not alter the registered extents. If the actual registered extents are 'wrong' when compared with the reality on the ground you are likely to have to all enter into transfers/exchanges of land Our PG 40 sups 3, 4 and 5 explain this in more detail for you&nbsp;<a href="https://www.gov.uk/government/collections/land-registration-practice-guides#guides-40-to-49">Land registration: Practice guides - GOV.UK</a>