Some questions to ask
Has the water supply ever run dry or close to dry
When was the septic tank put in, how often emptied if ever (never isn't a bad answer provided there haven't been blockages
Anyone else take water supply from the land or just over the boundary ( we found next door but ones water supply comes from just over the boundary from us on neighbours land, which means he can have cattle churning up ground and using sprays but we have to be really careful as the water is effective,y coming from our ground )
What is the fencing like ( costs a lot to do, one of the biggest costs). Can be a hassle if stock fom neighbours keep straying and if you want to keep stock
Anyone have shooting rights on the land as they can be separate to the land purchase
Anyone been renting the ground in recent years and on what terms
What is the mobile reception like and which company has best reception
Any rights of way or permissive paths
Any planning applications locally and check local plan for any longer terms plans for surrounding land
Access, is it undisputed and in your ownership, if not what are the arrangements, any past issues with it?
Some Of these will be on the standard questionnaire but the land ones not so much.