Additional BP cost to add turret to shuttle for ship build

[Oshaegda]

I was looking at building a shuttle for a small party, but I would like to add additional guns. The shuttle base frame currently costs 6 BP in the ship creation chapter, and I am thinking that if I add a turret to the base chassis that the modified shuttle should cost 8 BP. What do you all think? Does that seem balanced?

[Nixitur]

Check this out. It details how much it costs to add new weapon mounts.
Specifically, adding a new light weapon mount to a turret costs 5 BP.

[Dragonchess Player]

In the Core RAW, there is no way to add a turret to a ship. It either has one as part of the base frame or it doesn't.

Also, no Tiny or Small ship frames have turrets. They probably just don't have enough volume to include one (and the installed weapons). It's probably also a limiting factor for the starship combat system; most Tiny or Small ships are maneuverable enough that a turret is less needed.

[Nixitur]

Huh, that's not how I understood it at all. That sounds to me like saying that a ship doesn't have an aft firing arc because it doesn't list a mount in that arc for the base frame. For example, the Bulk Freighter doesn't list a mount in the starboard arc, but I would assume that you could add one to it by upgrading the ship. Similarly, I would expect to be able to add a turret mount to any ship, even if there isn't one listed in the base frame.
Furthermore, even though no Tiny or Small ship frame lists a turret, the paragraph on adding weapon mounts lists a limit of mounts per turret for Tiny and Small ships. It's unlikely that the writers would add that if those ships didn't have turrets at all. Sure, that could just be futureproofing, but given my previous example, I find it more likely that they do have turrets, but there just aren't any mounts on it yet. Or at least that you could add a turret to it with little or no extra cost.

[Perdue]

Use this site to build a starship:
http://jamesturneronline.net/starfinder-ship-builder/

[Styrofoam]

In the AP this exactly what was done. They added a turret to a shuttle. Check out the Hippocampus from the first AP book.

[rook1138]

Looks like you'd need to upgrade an existing mount (5 BP), or add a mount (3BP) and then upgrade to a turret (5bp). But you can't have more than 2 in an arc.

Core Rule Book Pg 305 wrote:

By spending 4 BP, the crew can upgrade a light weapon
mount in any of the aft, forward, port, or starboard arcs to a
heavy weapon mount. By spending 6 BP, the crew can upgrade
a light weapon mount on a turret to a heavy weapon mount. By
spending 5 Build Points, the crew can upgrade a heavy weapon
mount in any of the aft, forward, port, or starboard arcs to a
capital weapon mount. Heavy weapons can be mounted on only
Medium or larger starships. Capital weapons can be mounted on
only Huge or larger starships and can’t be mounted on turrets.

By spending 3 BP, the crew can fit a new light weapon mount
in any of the aft, forward, port, or starboard arcs with enough
free space. By spending 5 BP, the crew can fit a new light weapon
mount on a turret that has enough free space. Tiny and Small
starships can have only two weapon mounts per arc (and per
turret). Medium and Large starships can have only three weapon
mounts per arc (and per turret). Huge and larger starships can
have only four weapon mounts per arc (and per turret).