a. On th "planning issues" you need to distinghuish two things:
1. Planning issues for the actual property you are buying. Your solicitor will ensure that the property is compliant with planning. Well, technically, your solicitor will ensure that the seller properly documents (by architects certs etc.) that the property is compliant.
2. It is up to you to investigate the area in which you are buying. Only you can really do a good job on this - because only you know what matters to you. For example, if you were buying in a rural area, you might be delighted if a new motorway is going to go within a few hundred yards if you plan to commute; conversely, you might be put off the property if you wanted a secluded retreat.
In a city, you might be happy to see Mr. Stringfellow moving in (presumably there must be at least one person in favour) or it might put you off an area.
b On the architect issue, your solicitor might more usefully have said that you should get an architect, civil engineer or building surveyor. Their purpose is to inspect and report upon the physical condition of the property, so that there are no nasty surprises later.
a should not cost you. b obviously will.