All good points, especially those regarding purpose, location and preparation.
I had my drive installed about four years ago. Starts at about 24' wide at the street, then flares to what used to be the turn-around area and continues another 75 feet back to the new shop, widening all the way. Total is about 3700 square feet.
One estimate from a local reputable concrete company was $38,000, but might go up, based on what they found when they removed the existing blacktop.
I only got one estimate from a blacktop company, but it's one that I have known for years (but never used). They found some spongy conditions under the turn-around and suggested some Geo-Tex before the rock, which was an additional expense (only about $650) and the total was just under $17,000.
They ripped out the old driveway in less than a day. Did some of the prep work, found the spongy stuff, installed the Geo-Tex and the rock on the next day. Let it 'dry out' for a couple of weeks while they finished up another large project that had been put on hold, then came back and laid the new blacktop in a day. VERY happy with the results and the price.
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