The problem with tarmac is that often the tar years are miles away, there's a minimum quantity of tar to be bought. It's a very early start. Usually trying to be at the yard when it opens, often at about 7AM. It's hot, smelly and dirty. With the workers stinking of diesel for several days afterwards. As you paint diesel on to the rollers, wheelbarrow tyres, lorry and your shoes. To prevent the hot tar sticking to everything. It's also really hard to estimate how much tonnage you're going to need and disposing of any left overs, especially if it's gone a bit cold is a real pain.

So any company doing them will want to either do larger jobs or do several small jobs on one day. Having done all of the preparation for them in advance.

You maybe able to cut the costs by being flexible on when they do and do much of the preparation yourself.

I'd start by giving the drive a thorough spray with some good weedkiller. Having read the instructions and following the advice on it, leave it for about a week or two. Then depending on what your existing drive is made up of. Dig about a foot down or if it's concrete break it out, remove all of the big pieces. Then level the remainder. Wack it thoroughly, you can rent a wacker plate from say HSS (cheaper alternatives are available). Add a few tons of type 1 scalpings to it. Level and wack it again, thoroughly. Somewhere like Jewsons may just have some in stock and can deliver but usually they come from a quarry, cement yard and arranging delivery can be difficult.

You'll want them to put down about 2" of tarmac and you'll want that gap at the front of the drive and then ideally finishing 2-3 courses below the damp proof course.

You'll probably have to look at drainage as well. As the local councils and water companies don't like rain water running off onto the pavement.