The 5-minute challenge 
The good folks at SmashingMagazine have a great article “9 Steps To A Happy Relationship With Your Hosting Provider” that explains some pretty straight forward truths about the Hosting industry and is well worth taking 5 minutes to learn enough not to caught out by some crappy webhost that’s going to squeeze you in with a bajillion other sites all running at a snails-pace.
Check the fineprint, how long is the contract? refund policy, etc.
I signed with a massively popular budget host “JustHost” who offered a $2.95/month unlimited plan that included unlimited sites as well as space. They offered a no-quibble money-back guarantee which I ended up using after having my servers down every weekend for three in a row.
During the few months I was with them I experienced reasonable performance with no real lag compared to my hosting by VentraIP.
Web host support. Budget web hosts that offer 24/7 support and live-chat obviously have to cover their costs somehow and quality of support is one area that can see a massive difference in support services.
Don’t get tricked into thinking having live-chat is the sole reason for choosing a host. I had a host who offered live-chat at no extra cost, yet over approx 8 contacts I was not once able to have a question resolved without being first told to instead log a ticket with the support team. Questions were often left unanswered, ignored for what seemed a template response.
You may wish to check a potential hosting providers service by searching Google for the name of the provider & service/complaint etc. (i.e. type in “godaddy service” “justhost complaint”
Important factors to consider.
Speed does make a difference and is a factor in how Google ranks your site. A slow site can quickly turn off potential customers, studies have shown a significant number of browsers can exit the site within seconds if the speed is below expectations.
Safety & Security. Consider the effort put in to creating the site which in some cases can require daily maintenance indefinitely. Hosts use extremely powerful hardware but like all things nothing is guaranteed never to fail. If the worst happens can they restore the site from a backup? How recent are the backups? Are there tools available for DIY backup?
Budget hosting works on the principle of shared resources. Your site is on a server that also has dozens or hundreds of other people’s sites on it. The more that share the less that’s available, and due to the way they calculate the so-called ‘unlimited’ data, bandwith or similar, you might found your host notifying you are using more of your allocated resources (such as going over just 10% of the available CPU), they may shut down your site completely and insist you upgrade. Once again something to consider when comparing web hosting providers.