Hi Blocko.  Welcome to racing.  I've gone through the novice program over the last two years and am spending time looking for a first race-car myself, so would be happy to share info.    Most of the experienced racers recommend more of a baby-steps approach that usually involves doing the novice program by renting or borrowing a car, then easing into regular racing with something like a used Spec Miata or perhaps a Formula Ford or Formula Vee if you like that route.  There are many choices in theory but in practice the selection of used race cars is not great, at least not at beginner's prices. 

I see the DF Goblin is a bit like an Ariel Atom when completed.  I haven't seen this one before.  This is one of the more tricky cars to fit into CACC/SCCA classes.  Most of the local rules and classes, defined by CACC, the sanctioning body, are copied over from SCCA rules and there isn't much room in SCCA rules for this type.  While I'm no expert (by any measure), it looks to me like this car would go in the same category as a Locost or Lotus 7 type of car.  I'm not sure if there is an "anything goes" type of category in wheel to wheel racing (I'm pretty sure that you can Autocross in AMod or BMod with almost anything).  I've had a look at the SCCA GCR and for wheel to wheel racing (ie. not Solo) perhaps the class might be sports racing (specifically  P1 o P2) but it is hard to tell.

There are racing series where the rules are much simpler and more lenient that you can fit into with this car, but they don't race at Mission.  For example, the Chumpcar series, or LeMons endurance racing.  These series get as close as Olympia WA (The Ridge).

There's an article by Jen Horsey in the current edition of Ignition magazine called 'Don't build your first race car - buy built instead'. The first paragraph reads:

The best racing advice I ever got was to buy built. It sounds counter-intuitive - especially to the mechanically inclined who imagine weekends in the shop with friends when the daydream about starting a team. But if you survey a driver's meeting in just about any discipline, you'll find experienced racers generally agree on this point: for your first race car, don't build it. Buy built.

I have to agree. There are a lot of great deals out there on used race cars. Anyone who has built a car will tell you that you will never be able to sell it for much more than a fraction of what it costs to build. Why kill your bank account and all your spare time figuring out if it's the right sport for you, and whether or not you do want to invest that much time and money into it. Just getting your personal safety gear is going to set you back a few grand, much less the safety gear for the car, and that's before you even do anything else to it! Besides, let someone else take the depreciation hit!

Better yet, rent a few different race cars for your first few races and figure out what type of car you want to race? Try open wheel as well as closed wheel. They are very different racing experiences, and learning to race both will make you a much better driver.

The article goes on to justify the position and it's a good read. Unfortunately it's not available online yet, but when it is I'll provide a link.

Go with the advice of the seasoned veterans. If you want some opinions on what to buy, there is lots of help available on this forum.