Hey everyone i am not a great developer so have hired out someone to design my website which includes mysql databases. My question is how hard would it be for a pro developer to change the look and layout of the site once all the different functions are working and the site is complete? Also if i hire a designer to create a templet for the design in photoshop, would it be difficult to implement this new design into my website? What kind of format would the photoshopped templet need to be in to make it easy as possible?

i my own opinion if coding is clean and is not redundant then changing anything won't be too hard...

What kind of format would the photoshopped templet need to be in to make it easy as possible?

Well, a Photoshop template is going to be in PSD format - not being smug, but if he gave you just a JPG, that would not be helpful.

If the template is CODED using CSS - NOT TABLES - for layout, then redesigning and/or layout changes later would be a LOT easier as that is the beauty of CSS. Technically, you can change the layout of an entire website by changing just 1 file - the CSS.

LadynRed is right. I was doing a site recently that used koolPHP as it's content management system. The whole site was built with tables and it bugged me. I had to redesign the whole site with div's just so I could change little things.

ok so if i were to get someone to design the look of the site they could just make it as a layered photoshop PSD format and then my developers could take this and turn it into css??

Yes, that would be the best method.