I think you will be very happy. The gun shop was very thoughtful in reserving some ammo for purchasers.
You got a very fair price. Make sure you frequent that gun store as they are looking out for their customers. I paid for a new in the box P3AT earlier in the year $265 before sales tax or $289 out the door.
I advice I got was for pocket carry: clean it regularly, and lube the rails. There is a guy over at the KTOG.org website who is an expert on KelTec maintenance. He has a post on lubing the KelTec, that I recommend strongly.
http://goldenloki.com/gunsmith/keltec/lube.htm My first additional purchases were a KelTec brand extra magazine, some .380 Auto snap caps, and a small piece of leather to turn into a pocket hoster. I really have been surprised as how easy it is to carry this samll and light weight wonder. I really feel it is safe with one in the chamber.