Welcome!
A note about waiting to take the class, you may want to take it sooner, rather then later, due to the extremely long processing times for CHLs now.
I admit, scoring a perfect 250 on the range test is great to do (I did on mine), but it is not necessary to pass, and as of right now, getting your paperwork in in a timely manner is key, if you want to see plastic before the next Holiday season :)
You do not need to send off to DPS for a packet, the CHL Instructor will have them for you to complete.
Also, be sure to look into any discounts you are eligible for. There is a senior discount, I do not know the exact requirements off the top of my head, and there is also a veteran's discount, which is 1/2 off the $140 fee. There are also others, but those are the 2 I know of off the top of my head.
When you send your packet in, be sure to send it certified mail, or delivery confirmation or something, so you have proof that they received it, and the date on which they did. It has been rumored that packets that do not come in with any way of verifying receipt date may be occasionally shuffled to the end of the pile to give DPS a few extra days to meet their legal requirements on the timeline. No proof of this has ever been presented, however, why take the chance
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This forum is a great group of people, and you can get answers (or educated guesses
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See ya around!