Selling to Gorgio Shanua (the pink hair guy) wasn't that hard to do when I tried to legitimately flip a house for him. For this guide I used the Seller's House, which you can also use to earn the I'm The One Who Knocks achievement.
Basically Gorgio just wants a place to put some clothes, and "stylish" color that's inspired by his hair. Yes he's vain. He also wants a sauna, doesn't want a kitchen, and prefers bathtubs over showers.
After cleaning the house and selling everything, I used Scarlet Ceramic Tiles on the floor and I painted the walls Indian Rose. I did this for all the walls and floors EXCEPT FOR the Garage, Bathroom, and Sauna. The latter 2 I built after scrapping the original floorplan.
Where the kitchen was. I installed a washer and dryer and an AC unit. EZPZ.
The most work I did was redesign the walls for the master bedroom and 2 baths. After pocketing the money $$ in the hole in the floor, I tore down the walls for the master bath and basically just rebuilt them around that hole. That very conveniently makes space for a Linen Closet in the main hall, which satisfied his need for clothing space (Ta Da! He now became my top buyer!)
Then I tore down the wall separating the guest bath from the master bedroom, so it's now part of the new master bedroom. I put the walls separating the master bedroom from the redesigned master bath at about where the sliding door edge is, and made sure to connect that with the other walls, leaving room for a door. Voila! New master bathroom, with ample room for a Sauna and a Bathtub.
Make sure to tile and paint with Scarlet Ceramic and Indian Rose after putting the new walls in!
For the Master Bathroom I used light colored ceramic tiles for walls and floor (white, light blue, light yellow) and I used wood panels/tiles for the Sauna walls and floor. After that, just add some stylish glass doors (that's what I did just to be safe.)
I didn't take any original radiator plumbing out except for the bathrooms. Before selling I put a radiator in every room except the sauna, garage, and the new laundry area. I put a large radiator in the first big room where the fireplace used to be. I put a towel radiator in the new master bath for space efficiency.
I wound up selling to him for 37,000 Euros profit.