What are the pros and cons of buying a kit aircraft vs. a factory-built one?
The objective is very important.  You don't build an airplane because you want one faster or cheaper.  Neither is the case.  The kit won't be cheaper, and it'll take 1 to 2 thousand manhours, minimum, of your time (take the building time claim of any kit and double or triple it to get reality).
You build one for the experience of building one.  A lot of people who build aircraft go on to build another for that reason (the guy that built the homebuilt I own built two more after mine).
If money's an issue, the most cost effective and efficient way to keep flying after your training is to find one or two partners and buy the nicest creampuff Cessna 150 or similar aircraft you can find (really nice 150s go for around 30k).  With the fixed costs split 2 or 3 ways the expenses don't become painful (if you have to start making financial sacrifices, it takes away the fun - been there done that) and it'll be easy to sell when you want to get something bigger.
If you're mechanically handy and want to maintain an a/c yourself, buy a used homebuilt or LSA.   Only look at a kit because you want to experience the building of the kit.