Congrats on pulling the trigger on the 300 vs the 200. If you are like many of us, you'll be buying a higher end machine soon enough.
I use a nail apron as my finds pouch (88 cents), they last for a season or two.
My 1st shovel came from Lowes for $8 to $9 bucks
I upgraded to this shovel after 2 years, it's great for a coin shooter like me.
I get my gloves at Lowes (10 pack) for $10
I hunted my 1st 6 months without a pin pointer. I won't hunt without one now. Having one really speeds up the time you retrieve a target which allows you to dig more targets during a hunt.
I do have an expensive pair of headphones, but often hunt with a cheap pair of foam ended ones, especially in the hotter months.
Using headphones let's you be more discrete, hear more targets and it saves on battery life in lieu of using the speaker.
I did start with a $13 garden trowel, but moved up to a Lesche hand digging tool
My 1st pair of knee pads, lasted for 4 seasons, I just bought another pair at a home improvement store. I only use one on my right knee.
You need to get out there and dig some treasure or mucho clad so you can get the best gear "for you" to really enjoy the hobby.
This is a hobby that funds itself if you put the time in.
Good Luck & Happy Hunting.