Docking clamp to mount it to the exterior of the hull. Access via the docking hatches in the docking clamp.
It is nice that you have a solution for your Traveller universe; but no 'starter' ships come with docking clamps -- nor is it clear that an airlock is included with a clamp. Plus there are some other disadvantages to clamps:
A ship’s Thrust and jump capability must be
recalculated when another ship occupies its docking
clamp, using the combined tonnage of both ships. This
likely means the manoeuvre drive will be operating at a
lower Thrust and the jump capability is reduced.
The size of a docking clamp dictates the tonnage of the
ship it may attach as shown in the Docking Clamp table.
Docking clamps can be added to streamlined ships but
the ship becomes unstreamlined when another ship
is docked to it. Docking clamps alone do not affect a
streamlined configuration. It takes three full rounds to
release or clamp a ship of less than 2,000 tons, during
which time neither ship can expand any Thrust or make
any attack rolls. Larger ships take D3+3 rounds.
A party of Travellers is paying a noticeable opportunity cost for a 'Ships Boat' without dedicated Docking Space.
So that assumes several things that are not, imho, in evidence:
1) You are playing a campaign that requires moving from world to world rather than around a space faring single system
2) You need to go some place off the beaten path enough that no jump tender exists to pay to take it across for you.
3) Your players are dumb enough to take the small boat instead of the ship shares if they know the crew is getting a ship that can't take it.
or
3) The GM is a big enough prick to not tell the players that they are gonna open the campaign with a "get a ship adventure" that isn't compatible with carrying a small craft (like High N Dry).
1} Every -- to my knowledge -- published campaign, and many published adventures, require the Travellers to make at least one interstellar jump; often more than one. Expecting that a party will need to be able to travel to other systems is NOT an extraordinary expectation out of a sci-fi game named 'Traveller'.
2} No special 'jump tenders' are necessary; nor are many detailed in the published material. However, paying to have a 20 dTon Ship's Boat carried as freight for a single parsec jump is a minimum of 20kCr; more if the transporter requires payment for the extra 'bulk' of unusable space (10% or more?) around the oddly-shaped boat.
3} A Ship's boat is worth up to 10MCr; it is not unreasonable that a player might choose that over a 1MCr ship-share. Even if they turn around and sell (probably at less than full 'list price') the Boat, it is still extra effort that has to be made in-game. Contrasted with a
- 'Type A Free Trader' benefit worth 11MCr+; or an
- 'A2 Far Trader' benefit worth 12.9MCr+; or an
- 'Empress Marava' benefit worth 13.5MCR+; or a
- 'Type K Safari Ship' benefit worth 15MCr+; or a
- 'Type Y Yacht' benefit worth 15.5MCr+; or a
- 'Type L Lab Ship' benefit worth 28.8MCr+
It is distinctly a second-best choice.
3b} You are assuming the worst of a referee you have never met. There are good reasons to NOT start the players off with a ship, and to NOT give the party a free ship in the very first scenario. And whether the party gets an 'incompatible' ship or not, the Boat owner has to either pay to transport it, or pay to Berth it until the party
does have a ship; or sell it. Once the party does have a ship, they must decide whether carrying the Boat is worth the opportunity cost of the freight or passenger space it occupies -- and they might disagree with the Boat owner, which is needless friction from a 'benefit'.
The Boat owner CAN offset
some of the expense of moving the Boat if they carry freight while being carried as freight. This is probably a marginal savings at best. The 20 dTon Launch and the 40 dTon Slow Pinnace are probably the best choices for this.