It could do but as you have a clean credit file and assuming the 6 year registar has expired you can go with another high street lender and therefore reason for another application is that you have seen a better product / incentive / rate etc.(posted 7526 days ago)Going to a second lender would only generally effect borrowers of 100% + mortgages and hopefully from your past experience you would not be foolish enough to go for such a ridiculous %.
If you had been to 4 or 5 yes in a short period of time it could effect.
I again remind you of my last question in the previous posting - did you have any special conditions in your full and final settlement regarding other securitised properties with Nationwide. It is very important consideration and if you did you should sort this out before occuring more loans and charges on the property.