The differences between all grain and extract is with all grain you might worry about efficiency, the amount of the starch you convert to sugars and the amount of sugars you get out of the tun and into the pot so you may get a different beer than expected but at a lower cost. With extract you know how much sugars you will get because you pay someone to get them and guarantee that is what you get. Come on people, this isn't hard science and it isn't terribly difficult. It can be even easier if you forget the cooler and go directly to BIAB.
My original plan was to "graduate" from extract to BIAB. I just needed to get a 10-gallon brew kettle and a bag and I'd have been set. I was looking for a deal that matched my finances....
...and then it happened. A guy on Craigslist was selling out of most of his brewing equipment and the price was stupidly cheap: a refrigerator (ferm chamber or cold crash chamber or just to keep my filled kegs in), 16 22-oz bottles, 5-gal kettle, 2 glass carboys, an inkbird temp controller, big funnels, stainless spoon, autosiphon, a lot of odds and ends and....
...a mash tun. All of that for $150. Well. I couldn't get there fast enough. The fridge works fine, I've since sold the two carboys for $25, so I'm out $125 for what probably was $350 of stuff.
So--I had the mash tun, didn't have the bigger kettle I needed for BIAB, so there I was. Second all-grain brew coming up this weekend. I've got the grain, splurged on a Barley Crusher....I'm all ready to rock. I think.
Thankfully, I've proved the process of boiling to bottling or kegging, so my focus is on getting the all-grain portion to work effectively. My first efficiency was low (on the order of 60 percent, I think--working on understanding that better), I believe I know what to do differently this weekend.
***************
I am trained as a scientist. One part of science is isolating variables to see how they work. It's anathema (I just LOVE that word) to me to have a process where I cannot isolate the factors responsible for the results. It's like an experiment where you have multiple independent variables and you cannot determine which, if any, are responsible for the results.
So, for me--given this strange character flaw my scientific background has produced--to voluntarily choose a process with more variables than one can easily control, well, I can't. It's why I was perfectly comfortable with trying extract brewing first. Not only could I see if I wanted to pursue it further, it limited the things to which I needed to pay attention.