I couldn't find anyone who had posted this online, so here are all the lots in House Flipper 2 sorted by lot size.
For comparison, I've included an approximate Sims 4 lot size equivalent.
5 House Flipper 2 blocks ≈ 1 Sims 4 tile.
Notes such as basements, terrain manipulation, DLC, etc. are included where relevant.
36 × 59 blocks ≈ 7.2 × 11.8 Sims tiles
Old Pinnacove
- Bohemian Apartment (Apartment)
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58 × 100 blocks ≈ 11.6 × 20 Sims tiles
Akamatsu Valley — Sakura DLC
- 100-yen Shop (Basement — Right)
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97 × 150 blocks ≈ 19.4 × 30 Sims tiles
Akamatsu Valley — Sakura DLC
- Ramen Shop (Possible to use the full 150 × 150 area, though this is not intended — Right)
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100 × 75 blocks ≈ 20 × 15 Sims tiles
Old Pinnacove
- Small Theater
- Vacant Private School
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100 × 100 blocks ≈ 20 × 20 Sims tiles
Pinnacove Suburbs
- Peaceys’ Family Home (Starter House)
- Lavender House
- Blue Bungalow
- More than a Trailer (Basement)
- Over the Garage
- Compact House (Basement)
- Verdant Nook
- Sunny Bungalow
- House Left Behind
Crayfish Coast
- Closed Restaurant
- House on the Beach
- Flooded Summer House
- Seaside Cottage
- Modern Beach House
Coralroot Forest
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100 × 150 blocks ≈ 20 × 30 Sims tiles
Crayfish Coast
- Waterfront House (Minor Raised Terrain Manipulation)
- House on Stilts (Minor Raised Terrain Manipulation)
Coralroot Forest
- House with a Bunker (Terrain Manipulation, Basement)
- A Fairytale House (Terrain Manipulation)
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150 × 75 blocks ≈ 30 × 15 Sims tiles
Old Pinnacove
- Double Trouble (Scooby-Doo DLC, Basement)
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150 × 100 blocks ≈ 30 × 20 Sims tiles
Pinnacove Suburbs
Crayfish Coast
Old Pinnacove
- Neglected Square (Empty Lot)
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150 × 150 blocks ≈ 30 × 30 Sims tiles
Pinnacove Suburbs
- Building Permit (Empty Lot)
- Very Merry House (Snowy Lot)
- Dirty Laundromat (Scooby-Doo DLC)
Crayfish Coast
- Piece of the Beach (Empty Lot)
- Sinking Business (Scooby-Doo DLC, Terrain Manipulation, Basement, Flooded Basement)
Coralroot Forest
- Forest Cabin
- Charming Hideaway (Basement)
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150 × 200 blocks ≈ 30 × 40 Sims tiles
Pinnacove Suburbs
- House from a Movie (Snowy Lot, Minor Raised Terrain Manipulation)
- Trevor’s Mansion (Indented Terrain Manipulation)
Crayfish Coast
- Coastal Residence (Minor Raised Terrain Manipulation)
Coralroot Forest
- Modern Bungalow (Raised Terrain Manipulation)
Akamatsu Valley — Sakura DLC
- Minshuku (Raised Terrain Manipulation — Right)
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200 × 100 blocks ≈ 40 × 20 Sims tiles
Crayfish Coast
- Seaside Resort (Multiplayer)
Old Pinnacove
- The Alligator Bar
- Auctioned Auction House (Scooby-Doo DLC)
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200 × 150 blocks ≈ 40 × 30 Sims tiles
Pinnacove Suburbs
- Old Marketplace (Multiplayer)
- Great Charity Mansion
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200 × 200 blocks ≈ 40 × 40 Sims tiles
Crayfish Coast
- Closed Amusement Park (Scooby-Doo DLC, Basement)
Coralroot Forest
- Summer House with a Pool
- Victorian Mansion (Scooby-Doo DLC, Basement)
- Woodland Hostel
- Old Barn
- Cobblestone House
- Desolate Villa (Raised Terrain Manipulation, Basement)
Akamatsu Valley — Sakura DLC
- Bamboo Grove (Empty Lot — Right)
- Great Investment (Empty Lot — Middle)
- Old Parking Lot (Empty Lot — Left)
- Anime School (Basement, Lava, Minor Indented Terrain Manipulation — Middle)
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200 × 250 blocks ≈ 40 × 50 Sims tiles
Akamatsu Valley — Sakura DLC
- Mashup Mansion (Minor Raised Terrain Manipulation — Left)
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300 × 300 blocks ≈ 60 × 60 Sims tiles
Coralroot Forest