Selling

“	When you sell a tower, you get 80% of what you paid for it, including all the upgrade money you spent.	”
	~ BTD2 Round 28 Pre-Round Comment

Icon of the Sell Price category in the Monkey Lab

Selling is a game mechanic in the Bloons TD series and in Bloons Supermonkey 2 Mobile, introduced in Bloons Tower Defense. In the Bloons TD series, it removes towers in exchange for a percentage of the total amount of cash spent on placing and upgrading it.

Terminology

• Sellback: the raw amount of cash returned from selling a tower.
• Sellback rate: the percentage of a tower's total value that is returned as sellback.

Mechanics

Bloons TD series

Selling a tower instantly removes it from play. In cases where only a limited number of a tower type can be used at a time (such as in challenges in Bloons TD 5, in Bloons Monkey City in general, in challenges and Odyssey events in Bloons TD 6, or allies in Bloons Adventure Time TD), sold towers are restored and can be used again later. In cases where only a limited number of towers can be placed in total, sold towers will also restore slots. If a tower has no cash value (such as Special Agents, Sentries, and placeable Powers), it can still be "sold" to remove it, though it returns no cash.

Certain towers that absorb other towers through sacrificing will also absorb the total value of the towers sacrificed, thus absorbing their sellback by extension.

The default sellback rate is 70% in Bloons TD 6, Bloons Adventure Time TD, Bloons TD Battles 2, and the Flash version of Bloons TD Battles, while in all other games, the sellback rate is 80%. Depending on the game, some mechanics can increase the sellback rate globally or for certain towers:

• In Bloons TD 4, Monkey Tycoon increases the sellback rate from 80% to 100%.
• In the web version of Bloons TD 5 and in BTD5 Deluxe, Monkey Tycoon increases the sellback rate from 80% to 100%.
• In the mobile, PC, and console versions of BTD5, the Sell Price category of the Monkey Lab can be upgraded to increase the sellback rate from 80% to up to 99%.
• In Bloons Monkey City, the sellback rate can be increased by leveling up Monkey Tycoon Monkey Knowledge, increasing from 80% to 85% at Rank 3, 88% at Rank 8, and 90% at Rank 13.
• In BTD6 and Battles 2, certain upgrades increase the sellback rate:
  • +10% when in range of Favored Trades
  • +10% with the Banana Salvage upgrade (only applies to the Banana Farm)
• Also in BTD6, some Monkey Knowledge can increase the sellback rate:
  • +5% with Better Sell Deals
  • +2% with Flat Pack Buildings (only applies to the Monkey Village and Banana Farm)

In Bloons TD 5

The 0-0 Dart Monkey in the web version has a sellback of $159 on Medium instead of the expected $160.

In the web version, sellback is sometimes $1 less than the intended value due to rounding errors, even in scenarios where rounding is not necessary to calculate the intended sellback. This bug does not exist in Bloons TD 5 Deluxe or the mobile, PC, and console versions.

In Bloons TD 6

0-0-0 Sniper sellback value on Easy ($210 sellback)

In Bloons TD 6, sell prices take the post-rounding cost, which is calculated by multiplying by the sellback rate, then rounding up to the nearest whole number. For instance, a 1-0-0 Sniper on Easy costs $595, taking account the $300 base cost and $295 cost for Full Metal Jacket, and its sell value is $420 with 70% sellback.

Unlike in prior games, there is a hard cap on sellback at $10,000,000 and a soft cap on sellback rate at 95%, though the former is very obscure, as only the Rare Quincy Action Figure, Monkeyopolis, and Sun Temples can feasibly achieve a high enough value in normal gameplay.

The Champion Sentry and Level 18+ Creepy Idol have unique effects that activate upon being sold. These towers are allowed to be sold even in C.H.I.M.P.S. and in rulesets where selling is disabled, though the latter does not return any cash if so. Marine can also be sold in C.H.I.M.P.S but does not add an extra effect when sold.

The Rare Quincy Action Figure operates on different selling mechanics than other towers. Its value increases with each round that passes after Geraldo unlocks it at Level 2, meaning its sellback is based on the round it was unlocked on rather than the amount that was spent on it. It has a default sellback rate of 95%, which is increased to 100% with Better Sell Deals, making it the only tower that can bypass the sellback rate cap.

If selling is forcibly enabled for CHIMPS through the Challenge Editor, then towers can be sold, but no cash is returned. Additionally, there are a few unconventional scenarios in which towers can be forcibly sold regardless of mode or ruleset, even those owned by other players in Co-op. On Flooded Valley and Erosion, all land-only towers placed on a certain land spot will be sold if it is converted into water. All towers placed on frozen water via Arctic Wind will be sold if the frozen water is removed, which can be accomplished without selling via Support Chinook.

Lych restores HP whenever a tower is sold, with the amount depending on the sold towers' highest upgrade tiers rather than their sellback.

Bloons Supermonkey 2 Mobile

In Bloons Supermonkey 2 Mobile, powerups can be sold for Red Blops in the Lab. The value depends on the rarity:

• 1 star: 100
• 2 star: 300
• 3 star: 500

Sounds

There are no selling sounds for pre-BTD4 games.

When the player sells in BTD4 Generation games:

• File:TBA [coin dollop]

When the player sells in BTD5 Generation games:

• [coin clinking]

When the player sells a powerup in BSM2 Mobile:

• File:TBA [TBA]

When the player sells in BTD6 Generation games:

• [cash shake]

Trivia

• In all game generations, at least from Bloons TD 4 Generation onwards, the selling sound is always the same for games sharing the same generation, but is different in each distinct game generation.
• Selling is disabled during the tutorial sequence of Bloons Monkey City on the first tile in both versions. On the Flash version, the Sell button is not visible, but the Dart Monkeys can still be sold by pressing the Backspace key on the keyboard, meaning that it is possible to lose the tutorial, although the game will still require the player to capture said tile first to progress. They cannot be selected nor sold in BMC Mobile during the first tile capture.
• The first community discovery of a tower in BTD6 other than Rare Quincy Action Figure to reach the $10,000,000 sell cap is a Monkeyopolis, by the use of a glitch related to Portable Lake stacking to 20+ towers causing placed towers to consume no footprint, shown here.
• In Bloons TD Battles 2, the sell button has an added exclamation point.
• According to Ninja Kiwi, that when sold, towers pack up their things and go home.