Furniture Guide

Kind of messy/long if anyone wants to improve on it.
== Purchasing Furniture ==
In order to buy furniture you must go to the furniture dealer near the top of the village, right of the waterfall.
Step 1: 
사기 - Buy
스탬프 특전 - Stamp Benefits
팔기 - Sell
상품 받기 - Receive Item
Step 2:
소재로 구입 - Purchase with Material (Craft it) 
제니로 구입 - Purchase with Direct (Without Crafting, more costly and receives no stamps)
엑스트라 구입 (소재) - Extra Purchase (With Material)
엑스트라 구입 (제니) - Extra Purchase (Direct)
Step 3:
Ceiling Decorations
Wall Decorations
Floor Decorations
There is a fourth option in the without crafting (both extra and regular) options as well. They allow you to buy cat farm supplies. I do not know the difference between extra and regular. The items seem slightly different for furniture, but are the same for the car farm supplies.
== Placing Furniture ==
Step one, go to your house: second option at the stairs left of the tavern.
Next, press 3 after moving out of the doorway to place furniture or walk to the storage box. A pop up message will appear confirming and telling you that it will kick anyone else inside the house. More controls listed in the picture bellow on the left.
Next, right click the storage box to select which furniture to pop out. First choice is selecting which, second is selling.
After selecting which furniture it spawns at the door space, click and drag to place and use 4 and 6 to rotate furniture.
To enter a friends house, press e on the bulletin outside: the first option is to enter house by name, the second by character ID. 
To invite friends, click on the bulletin board. (needs confirmation, I'll probably do it later)
== Stamps and Cat Farm Supplies ==
Stamps are received from buying furniture and are used for cat farm upgrades and a few other items, the other guide can be found here: Stamp Guide (coming soon) or http://mhfn00bs.proboards.com/index.cgi?board=tips&action=display&thread=10 
So here are hotshotz79's results;
Crafted a Rare 6 Decoration piece for 17,800z + materials
Received 9x Stamps 
Bought a Glowing Lamp Post for 17,800z - no materials
Received 0x Stamps
Crafted a plant for under 1000z + materials
Received 0x stamps
Crafted a Bulldrome Floor carpet 3000z~ish + material
Received 1x stamps
So the conclusion so far is in order to receive stamps you have to spent more then 2000z-3000z and it has to be crafted. 
To upgrade your cat farm, simply go to the stamp benefits page (2nd option when talking to furniture man), and press the confirm button and choose the confirm option when prompted. A list of upgrades should come up, here are the approximate translations: 
Page 1/3 
1 - 갤러리 심사권 = Gallery simsagwon (Check Gallery Score) 
2 - 갤러리 대회권 = gallery daehoegwon (Exhibit; turn in furniture for rewards) 
3 - 갤러리 대회권G = gallery daehoegwonG (Exhibit G; turn in furniture for rewards G) 
4 - 럭키 물뿌리개 ★★ = Lucky Sprinkling can Rank 2 
5 - 럭키 물뿌리개 ★★★ = Lucky Sprinkling can Rank 3 
6 - 럭키 빗자루 ★★ = Lucky broom Rank 2 
7 - 럭키 빗자루 ★★★ = Lucky broom Rank 3 
(Gallery = the house where you place your decorations and furniture)
Page 2/3
1 - 럭키 잠자리채 ★★ = Lucky Bug Catcher Rank 2 
2 - 럭키 잠자리채 ★★★ = Lucky Bug Catcher Rank 3 
3 - 럭키 고기굽기 기구 ★★ = Lucky Meat burning equipment Rank 2 
4 - 럭키 고기굽기 기구 ★★★ = Lucky Meat burning equipment Rank 3 
5 - 럭키 곡괭이 ★★ = Lucky Pickaxe Rank 2 
6 - 럭키 곡괭이 ★★★ = Lucky Pickaxe Rank 3 
7 - 럭키 먀옹절임단지 ★★= Lucky Planting Service Rank 2 
Page 3/3
1 - 럭키 먀옹절임단지 ★★★ = Lucky Planting Service Rank 3
2 - 가구점의 진열 ★ = Furniture store shelf
3 - 가구점의 진열 ★★ = Furniture store shelf
4 - 가구점의 진열 ★★★ = Furniture store shelf
5 - 가구점의 진열 ★★★★ = Furniture store shelf
6 - 가구점의 진열 ★★★★★ = Furniture store shelf
7 - New added option in Update 4.0 (Unknown as of yet)
(Furniture store shelf = Unlocks more decoration to craft and/or buy)
By going to the 4th option of the furniture man's "buy without crafting," you can buy cat farm supplies. These supplies temporarily increase your chances of rare items from the garden so you must rebuy them often. Here is the list of the supplies that he sells: 
물뿌리기 - Watering Can (For Herbs) 
빗자루 - Broom (For Cleaning) 
고기 굽기 - Burning Meat Equipment (For Cooking) 
곡괭이 - Pickaxe (For Mining) 
잠자리채 - Bug Net (For Insects) 
먀옹절임단지 - Flower service
== Credit: ==
Most, if not all, credit goes to hotshotz79, taken from http://mhfn00bs.proboards.com/index.cgi?board=tips&action=display&thread=35 with permission.