Rule #2 - Detach Yourself
You will not live in the property you buy, so whether you personally like it shouldn't be the primary consideration!
It needs to be in a good enough condition that you would be willing to live in it...perhaps not long term, but live in it nonetheless...but that isn't the same thing as being to your personal tastes or being somewhere you would ideally want to live
As an aside, those Landlords who think "It'll do for a tenant" are getting it spectacularly wrong and funnily enough will usually be the ones who complain that they never get tenants willing to stay beyond the initial 6 months...
Anyway, back to the main point... this is a business transaction, and as such the question is whether it works from a business perspective?
A classic example being Plains Farm– it's not my favourite place, but I've never known a Landlord with a decent property there be short of tenants!