Should I get a survey?
Maximum peace of mind will be gained by hiring a surveyor to do a boundary inspection for you. I'm sure you have a home inspection planned...get the land professionals to check out the boundary (or rather the structures and features that are close to it) for you. that way you'll know for sure.
If you don't have the time to do this, or it's not in the budget, try to find an existing survey plan of the property. If you're in the GTA we offer the largest database of existing plans for you to search (www.protectyourboundaries.ca). You can also ask the seller and the neighbours if they have one. Failing that call your local surveyors to see if they have done work on the property.
Ideally you're looking for one that was done after the fence was built which will show the fence location in relation to the boundary. If not, as long as the survey plan shows the building on the property, you can use the measurements (between building and boundary) to approximate where the boundary is on the ground. Obviously this is not as accurate as getting a surveyor to do it but it's better than doing nothing at all.