To upgrade your house, you need to get 200,000 G and 2000 Lumber, then talk to Neumann. He'll upgrade your house. It'll take 10 game-days to build.
In your house, you can have a Small Refrigerator, Small Shelves, Small Kitchen, and Small Table. In your upgraded house, you gain the Forge (where you can upgrade tools, and make weapons and accessories) and the Pharmacy, where you can make medicines and potions. Also in the upgraded house, you can buy the Double Bed, Large Refrigerator, Large Shelves, Large Kitchen, and Large Table from Ivan. You need to have your house upgraded and buy the Double Bed before you can marry anyone.
Sadly, I cannot help you with RP replenishing ingredients... I don't really use them myself. ^.^; I prefer to have ripe crops handy in my fields, so they'll give me Runes.
Large yogurt gives you 15 RP, but you need to buy the yogurt maker from Ivan before you can make it. Then you need to tame some cows in Mt. Gigant and level them up to about 7 or 8 by brushing them every day and making sure they have feed in their huts at 6 am. Then they'll produce the large milk and you can put it into your yogurt maker to get yogurt. Oh, and you can stop brushing your cows when they reach FP 10.
Fried eggs from the pub also give you 15 RP. Once you've saved enough money to build your house, you'll probably be making enough to buy them. I prefer fried eggs over yogurt because they take only 30 real life seconds to digest before you can eat another. L. yogurt takes 90 seconds. Also, each cow produces milk only once every 3 (or 4?) days.
I suggest you grow crops in Carmite and other dungeons for RP. Also on your farm. Just leave them there without harvesting, and you'll get a new rune for each 3x3 plot each day. If you don't have all the wood you need to upgrade your house and build as many monster huts as you need, then leave most of Toros unplowed and clean it out every day or every other day. It's a great place to find wood, especially the areas upstairs. Don't forget the room where you need to break a rock to get in - lots of wood shows up there.