Basic boat hull.

main page
1) Create some simple (suitable) object – here, just 5 cubes. Create one, select opposite faces, extrude normal > 2 (press+hold shift to constrain to 1wu steps), repeat (use shift+D) (or Scale Z orig cube, then Cut / Connect longitudinal edges?)
Since am going to use Vmirror, select all relevant faces and dissolve – apply Tools | VM > Create.
If you want to make a particular hull shape and you have drawings, with cross sections, then spacing the 'block extrusions' at the appropriate positions along the length of the hull would make more sense that having equi-spaced / equal thickness 'blocks'  (Obviously, if the cross-sections / stations are equi-spaced, then that's different :) )

2) Various ways of making the ‘pointy bit’ for the bows – I selected the edge shown, dissolved, selected the whole object and used Object | Cleanup – but use any way you like / prefer to do this.

3) Result after doing (2) – have rotated the screen grab so’s not to waste 'strip' space.

4) Now going to form the overall shape (plan) of the deck, by adjusting the relevant geom. - again, if you have a (reference) drawing, then this could easily be used at this stage. (Import ref. pic. via Image Plane, rotate as necessary, move -Y (a long way) and lock via Window | Geometry Graph - so you don't keep inadvertently selecting the Im.Plane
View Y, Ortho. Use Vert | Move Free or Tweak or Vert | Move > X (if you want to keep stuff aligned along the cross-section planes) on all the relevant ‘deck’ verts – 5 of ‘em in this example. I used Tweak as I wasn't bothered about keeping cross-sectional planes ‘flat / square’ to the boat's longitudinal axis (Z in this ex)
Move these verts around until you’ve got a deck shape you’re satisfied with. I stopped at the stage shown.
If you think there's going to be insufficent cross-sections to accurately describe the shape you're after, then it's probably easier to add new loops
before adjusting the 'deck line' verts - although you probably won't know until after doing a bit of deck vert tweaking :) - you'll probably find Edge | Slide is a good friend after forming the new loops?

5) View X, ortho. As am initially going for a ‘hard chine’ type hull, I want to move the ‘corner bits’ up a bit. Select verts shown and use Vert | Move Y. Now got the basic ‘V’ of the hull. (Again, you could have used Tweak or  Move Free)

6) Using Tweak, I messed around a bit to get a slightly smoother keel and chine line – again, View X ortho and as all of this is done with VM on – the other side is being altered as well. (I know the shape won’t win any prizes or any races – we’re talking basics here…)

(5 / 6 could just be a single stage, using whatever Move type tool you want, of course )
7) At this stage, we’ve got a deck line that’s vaguely accepable – but the chine corner is still straight.

8) View –Y (minusY), Ortho, w/frame. As we’re now looking at the underside of the hull, it’s easy to select the verts that need adjusting. I used w/fr as imo it helps with alignment – use whatever you prefer.(Sometimes I temporarily make edges hard, so they're a different colour and therefore easier to pick out / select when part of a group - might've done it here if it'd been a more complex situation)

9) After adjusting the first 3 verts from the bows - using tweak

10) All 5 verts now adjusted - I suppose if you'd wanted a uniform difference between the chine and deck lines, then using Move X on all the relevant verts might have been an idea - I didn't bother.

11) Shaded view of this stage.
12) another view showing basic shape – could stop here if only want a hull of this shape (with additional geom. of course to stop it going ‘blobby’ during smoothing)

13) The basic shape as shown in (12) lends itself to further (relatively simple) mods. If you create new mid-way edges by using Edge | Connect, then this additional geom will let you convert this hull into a round bilge shape – or, if you want to ‘flare’ the sides / bottom of a hard chine hull, they’ll also let you do that.
Here, I’ve adjusted (with Tweak, view Z, -Z, ortho) the new edges on the RH half (only) of the original hull shape to form a basic round hull. I didn’t bother altering the LH half – moving the new hull side verts (on LH half of the pic) >  X (slightly) would create a slight ‘flare’ – similarly, moving the new underside verts slightly Y would do a similar job for the bottom of the (hard chine) hull.

14) Another view showing the adjustments on one half of the hull.(upper side only)
15 – 17) Rounded hull shape, with additional mech bevels on appropriate edges to hold the shape during (1x) smoothing.

18 – 20) Similar pix of a hard chine version.

Note that the only time I really needed to freeze VM was for (13) – because I wanted to show 2 different results on the same object.
This is a very basic tut for making simple boat hull(s) - was originally done in response to a request at ODF, but I thought I'd also include it here - in a slightly modified form.