What you need the most is information. The info in this thread of unbelievable. There are discussions of every topic you could think of.
As far as being able to cut them, absolutely. You cut to the length you need, put on a gilbert plug and you have a "custom set." But that is just the beginning. You have to understand amp load, voltage drop etc. There are endless companies you can buy from. I can honestly say, I don;t recall getting anything from Christmas Lights Etc. There are products that are unique to companies such as Holidynamics with their light links - really cool, the mixed noble garland etc. Light Links are really cool, but do not do well here in my market.
I am not going to pitch one company to you either way, but it would benefit you to contact the (are we still referring to them as the big 2). I am affiliated with Holidynamics. If you contact them, you are going to want to talk with Mike Marlow. (You can search Holiday Bright Lights as well and you will see an abundance of info on this thread. It is the same company, they just under went some reorganizing and part of that was a name change.) They also offer some great training. However, if you are more into the C-9's as I am, they are not really big into them. They offer more of a specialized line, ie light links and such. check their website out you will see what I mean.
CDI (Christmas Decor Inc) is more the c-9 company. They offer some really great colors, including LED, and from what I have read here, some of the best training available, but they are a full franchise and expensive to become part of.
Brite Ideas, well, I will just say that when I was at their show room back in 2009, I was not impressed and will leave it at that.
I also deal with Christmas Designers Inc. I like the response I have gotten from them with situations, and I like their products. They also offer a book on starting a Christmas Lighting Business, $200.00.
As I mentioned, lots of info here, and most likely enough to answer all of your current questions, and in the mean time, create many many more. I would also suggest looking for threads that Dave G and TurfHokie have either started or chimed in on.
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