If you're one of those people who enjoy the trouble and expense of an expansive lawn, need to cover a large area, and aren't made of money, there is no question sowing seed is the way to go.
Bermuda grass is a great turf grass, but sowing seed can be quite frustrating.
First, Bermuda seed requires warm temperatures to germinate, typically sustained high's exceeding 82 F. In my neck of the woods that coincides with the "dry season".
Bermuda seed is tiny and the emerging seedling is as fine as a human hair (maybe thinner). Combine that with heat, summer sun, and a dry season and your chances of success are reduced.
To be successful sowing Bermuda requires more than throwing seed out and scratching it in. The seeds need to be lightly watered several times daily and should be protected from the burning rays of the sun at least for the first couple of weeks after germination. Methods to protect from "sunburn" include lightly spreading hay or straw over the area or putting down burlap on top. The former usually introduces weed seeds that will germinate, the latter is prohibitively expensive but is the best way.
Oh, what to do, what to do...
I strongly recommend that you break down your sowing task into smaller segments. Instead of tackling the entire front lawn try a 20 ft x 20 ft section at a time. After a couple of weeks and your new seed has emerged and grown past "sunburn" stage sow another section, and so on.
I think you'll be a lot more successful and you won't have to spend hundreds of dollars on burlap either!
The same holds true for sod. I'd rather sod than sow seed, instant lawns are nice. With prices running $150 - $200 per pallet for about 400 sq. ft. try laying sod - which is a tough, dirty job anyhow - in the same manner.
Typical homeowner lots average 5,000 sq ft or in sod dollars, maybe 3 grand. Purchase sod a pallet or two at a time as you can afford it. I promise you that you'll have as much fun as you can stand laying sod using this approach! Don't bite off more than you can chew...