If your goal is to have a website that is a business and not just to share your most recent trip to Jellystone than I would say without question you invest some of your budget in hiring a professional. Just like the plumber or the electrition its not a matter of when everything is working that is in question, but what happens when things(and they always do) start to get a little screwy. If you opted to use a templated site than you are strapped to that template. The repair and the workaround always lies within the code, which of course now leads us to the poor soul who has to try to pick apart what has gone wrong. My motto is let the business owner be the business owner and let the web developer handle what he does best. With that said feel free to contact us at email@example.com if we can help you in your process. Thanks.
You may contact me by availing our services through email - firstname.lastname@example.org
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My company is right in the middle... we do everything you need done from SEO to Domain Registration to Hosting to Maintenance to Scripting, but it is not 100% custom. We employ a template company to make the basic design then we customize it for the clients specific needs. We do not write scripts from scratch, but we can modify very powerful scripts to do exactly what you need them to do. Scripts like oscommerce, wordpress, and even php nuke (although i prefer wordpress as a cms to phpnuke).
My advice... dont get caught up in the "templates are bad" debate. They can be bad, dont get me wrong... but they can also be friggin awsome in the right hands. Budget about a grand for the initial set up stage and then get a decent host (if your designer/scripter doesnt do it) because even though $10 a month sounds good at first, if your seo is good you will be paying out the wazoo for bandwidth overages within a year of going live. I highly suggest you keep your site with your designer if they do hosting... all the time i see really well made sites get butchered by laymen who didnt set it up originally when they are making updates to the site. What we do is alway host the site after the initial design is complete. Our name is at the bottom and if i cannot vouch for the updates then i dont want my companies name on it.