Most Crowntails I have found in the LFS are not of show quality, and therefore usually listed at $3.99-$4.99 or so. Breeders that list online and such usually sell show-quality CTs and that is why they're more expensive. I think they're certainly worth the money.
$13.99 is a ripoff IMO.
You might get lucky and be able to find fancy bettas at the LFS. You have a better shot of spotting them at the smaller family-owned type fish stores. You'd be hard pressed to find anything other than a veiltail at PetSmart or other major chain stores.
I'm lucky, I have two LFS's that carry...
Definitely go with something such as a desk light or hood fixture so that you don't run the risk of overheating your Betta with regular heaters. They're not reliable. The safest thing to do is heat the room, and not the bowl.
Bettas don't really care for current and don't need filtration, which is why filters are rarely used by Betta owners. Your 2.5g bowl would be just fine for a Betta. You can get real nice "fancy" Bettas online. Some of my members at my site are also breeding and have some they're getting ready...
My name is Jenny, and I just joined here. I have 1 dwarf puffer tank and 3 betta habitats at present. I'm moving to Austin in May from Florida and taking them all with me, and have another one waiting for me when I get there as my birthday present. It's a 5g Jebo with a power compact light...