In practice a higher load rating tire was also a wider tire. In this system a tire had a letter, optionally followed by R for radial tires, followed by the aspect ratio, a dash and the diameter-C78-15 or CR78-15 for bias and radial respectively.
Planning your project. Ground floor extensions are typically more affordable than converting the loft or excavating basement space. Renovation costs for a same level extension are roughly between $60,000 and $200,000 depending on your situation, including material, labour and project management (ready to move in). same level house extension in New Zealand will cost approximately $60,000 to $200,000+. Adding a room or extending your living area on the ground floor are affordable ways of creating more space.
Perhaps $500 for materials, and whatever your Hvac guy wants to charge for labor (usually some multiple of his diesel-super-duty 4x4's monthly payment). If you need a steel trunkline & ducts, the labor & materials costs jump very quickly. The $5k quote, if applied to a typical 1500 sq ft house would be fairly high retail for just an air conditioner. Equipment costs would be perhaps $2k of that $5k, unless you wanted one of the fancy brands.