This is a complex but well worth it redstone vending machine. You put a emerald in the bottom and click on the button below the item frame to get what's in the item frame.

Inspired by Mr. Crayfish

Step 1: Step 1: Getting the Materials

You will need

Hoppers
redstone dust
redstone torches
redstone repeaters
redstone comparators
4 beds
63 emeralds
chests
droppers
dispensers
fireworks
sticky pistons
blocks of redstone
buttons
ladders
3 item frames
3 different items
block of choice (besides redstone block)

Step 2: Step 2: Getting Started

To start you will need to dig a 3x4 hole, three blocks deep.

Step 3: Step 3: It's All About the Money

First choose one of the 3 block long sides to be your front. In the bottom middle of the front, place a chest and put 2 hoppers on top (PS you’ll have to crouch to place the hoppers). Then, place 2 block going from the chest to the back. On the block closest to the chest place a redstone comparator and in front of it a redstone repeater(make sure they’re facing the right way).

Step 4: Step 4: Starting to Get "complicated"

For this step place a block in front of the redstone repeater, one block above the ground, and place redstone dust beneath it.

Step 5: Step 5: It's Working

Go to the front of the machine and place a block in the back bottom left corner and place a redstone torch on the side facing the front. Go on the block you just made and place a redstone repeater in front of the redstone torch. In front of the repeater place a block and put redstone dust on top.

Step 6: Step 6: It's Not So Hard

Go to the front and on the right side of the comparator, place a block of redstone with redstone dust on it.

Step 7: Step 7: Scam Catcher

For this step, right click on the hopper closest to the chest and put your 63 emeralds in the first slot and your beds in the other four.

Step 8: Step 8: Insert Here

Put a block on both sides of the top hopper. Then, build up 2 higher on each block and put one in the top middle leaving a one block gap in the middle.

Step 9: Step 9: What Ya Gonna Get?

On the top row of blocks you just made, place three buttons on the front and place a row of blocks behind the “n” shape you made making a stair like shape and place repeaters facing the back on top of that row.

Step 10: Step 10: Attack of the Torches

Behind the new repeaters place a row of blocks with redstone torches on the back face.

Step 11: Step 11: VIP (Very Important Part)

On top of the new redstone torches place a row of blocks. On the blocks right below the new set of blocks, place a row of redstone repeaters that should light up.

Step 12: Step 12: It's What Makes It Work

Above the non-lit repeaters, place a row of blocks. On top of that row, place a row of redstone torches.

Step 13: Step 13: Getting the Items (from the Vending Machine)

For this step, go to the front and place a row of blocks on top of the row with buttons. Place a row of droppers facing the front and put ladders on the front of that.(PS to place the ladders you’ll need to crouch.)

Step 14: Step 14: Digging Deeper

Go to the back of the hole, and dig out a 3x3x3 hole.

Step 15: Step 15: More Work

Build 2 rows of blocks at the bottom back of the new hole.

Step 16: Step 16: More Redstone

First, place block on the right side of the 2 rows you just made and place redstone dust on that. Then, place a redstone torch on the block next to it on the side facing the back. Then, place 2 comparators facing the way shown with redstone dust in the back right corner and a repeater next to it in the way shown.

Step 17: Step 17: the Pistons

First, place a sticky piston with the sticky side to the front then place a block of redstone on the sticky side.

Step 18: Step 18: Almost There

Go to the row of redstone torches and build 2 row of blocks going towards the back.

Step 19: Step 19: Attack of the Redstone

Go to the redstone block attached to the piston and dig down 2 block right to the left. Go in that hole and dig one block in the same direction. Run redstone dust up it and the place one on the block to the right of the one block deep space. Build a block over the 2 deep space and one to the back. Run the redstone up that and across the row you made earlier closest that’s to the back .

Step 20: Step 20: the Last Piston

On the side of the block over the 2 deep space facing the front, place a redstone torch. To the left of it, place a sticky piston facing the front. place a block on the sticky side.

Step 21: Step 21: Small Things Matter

3 blocks from the front, make a row of blocks across the hole and put redstone dust on top of it.

Step 22: Step 22: I'm Runnin' Out of Redstone

Place a repeater on the left side of the new redstone facing the way shown. Next, dig out the block in front of the repeater, the one under the block the sticky piston is holding, and the one to the right of the repeater.

Step 23: Step 23: Too Much Redstone

For this step, run redstone dust through the hole you just dug and place a block to connect the redstone to the block with the redstone torch on it.

Step 24: Step 24: Separate Paths

Place 2 blocks above the redstone piece you just made to separate the square shaped piece.

Step 25: Step 25: the Options

In between the droppers and the buttons, place a row of item frames. Right clicking on the item frames with something in your hand will put it in the item frames as shown.