I had plan to sell my flat last year, but this didn't happen. Because of my current circumstances I had to rent it out... I got permission to rent from my current lender but my deal runs out in January and I'll have to swap to a buy to let mortgage. Excuse my ignorance, but will I end up paying much more on a buy to let mortgage? Ideally I want to pay less in the current climate (though I was on a really low rate so date that would happen anyway).