Moet, I personally use HostGator for hosting (they allow adult material), and NameCheap for domain registrations. That's not to say they're the only 2 options, but they're both fairly reliable.
I know a woman that was quoted $2000 for a web site, by the time it was all over they nickeled and dimed her to well over $5000. Try the DIY route first, it is the cheapest by far.
I've seen this happen as well. Here are a few things to keep in mind:
1. A quote is a quote, not an estimate. They (web designers/developers) should not raise the price more than a reasonable pre-set amount unless both agreed upon. Generally, about 5% +/- is reasonable in my opinion. Otherwise they're not very good at quoting, which is definitely a red flag.
That being said, this assumes the project scope does not change.
2. All changes should be discussed before proceeding, as they will likely change the cost of the project. I've had clients literally request over 100 hours of additions and changes to a web project (original quote was 40 hours), then were shocked when I mentioned I would charge for the additional hours. Major changes cost money.
3. If in doubt, talk to them.
Never, NEVER assume. Even changes that seem small may require significant changes in the coding. The reverse is also true, where seemingly large changes may take very little time. Communication is key.
4. Perhaps the most important,
MAKE SURE TO HAVE A COMPREHENSIVE CONTRACTOR AGREEMENT. Be sure to include clauses like transfer of ownership/copyright, exclusive usage, what happens if they're late, what the quote covers, how much additional changes cost, policy on bug fixes, etc.
If you decide on the DIY route, Wordpress works well as a base to build upon. It's free too! You can find many free downloadable themes to use as well (to change the look of the site). We actually built TheRouge.ca on Wordpress and it's working incredibly well so far, although to be fair it did require quite a bit of custom coding. That being said, it's more complex than the average website.