You will need to do some researching first. Has anyone in the neighborhood had their roof replaced recently? You should talk to them and see which contractor they used and ask how satisfied they were (see our Reviews pages). Also, read our blog on Choosing a Roofing Contractor.
Not all contractors are the same, so it is advisable to get estimates before deciding which roofing company to choose. Keep in mind that the lowest price might not be your best option (you get what you pay for!) When speaking to contractors, take note of any pertinent information, ask about the roofing materials they use, warranties, and any additional charges that may apply.
What kind of roof you have, whether your roof is sloped or flat, and what kinds of materials are used greatly affect costs. You will want to consult your contractor for the best materials. You will want the longest lasting roofing shingles, because hopefully then you won't have to replace as often. You may find the cost may be a little higher initially, but you could save hundreds or thousands in the long run.
Asphalt shingles are the most commonly used material to build a roof and are cost efficient and generally guaranteed to last 20-30 years, while wood shingles can last up to 25 years but need regular maintenance. There is metal, tile, and terra cotta as well. The slate roof is the longest lasting; however, it is also the most expensive. Usually upscale homes have these sorts of roofs and depending on the quality, they can last up to 200 years.
There are different quality asphalt shingles too, even by the same manufacturer. Like anything, the shingles with the highest warranty, the nicest look, and all the extra options, will of course cost more than standard economy shingles.
To do things right it will take some time. Even if you require someone to come and repair a leak, then find a contractor who will do it right the first time. When searching for a roofer there are several things to consider. Make sure that they are licensed and insured and have verifiable roofing credentials. Find out how long they've been in business, and check their references. Also check them out with the Better Business Bureau (Emmons Roofing & Siding is Accredited and Rated A+ by the Better Business Bureau).