Second visit: survey and purchase ~ Ao Nui

Tetis had been inspected at construction and at regular intervals by the Portuguese marine authorities, so I had no concerns about safety of the electricity, gas, and fuel installations. Knowing that, I chose to hire an old acquitance who is very knowledgeable about Wharram architecture and construction methods, having built a Pahi 42 himself and lived most of his life in it. I met him and the owner-builder (turns out they already knew each other, too) in Lisbon and, over the next day and a half, we surveyed the boat together. He found a few important defects which will need fixing:

Beam 4 does not lie evenly on its external starboard support blocks: there's a ~2 mm separation between the beam and the forward block, so all effort is against the aft block. He recommends filling the gap with PVC plate of appropriate thickness.
Rudders are not glassed. The port rudder has a knock. The wood is still sound, but it needs fixing (sand with 80 grit sandpaper, paint one hand of epoxy, fill with epoxy putty (epoxy thickened with microspheres).
The chainplates are misaligned; the starboard ones seriously so (about 12º). They should be repositioned or reinforced on the inside. [After some research, I'm not convinced this is the best way to go: chainplate misalignment seems to be a common cause of rigging failure -- I've asked at WB&F].
There's no chain for the 2nd anchor. He recommends 5m of chain and 50m of 16mm line.
To ensure I can get the headstay taut and fixed, he recommends adding additional line or cables from its foot to the stems (there are a couple of suitably placed padeyes there).
He reckons the shrouds are too close to the mast and recommends placing running backstays to obtain enough tension in the headstay. [Note: I later verified the rig is as per plans and that Tiki 30 owners have no complaint on this -- I believe he got mistaken by the pitch of the boat on the beach. I'll do this only if I have serious problems with headstay tension].
He recommends painting all wood with damaged paint before winter.
Stanchion attachment is weak -- needs reinforcing. I have decided to remove the stanchions instead, as the proper way to stay on the boat is lifeline and tether.

Less important issues I can work on over time:

It would be better to glass the rudders.
Most wooden pieces are left with sharp edges. Where a rounded edge can be made it should be preferred, as that helps paint stay in place.
He generally finds the cleats (made to plans) insufficient and recommends sizing them up.
He recommends making anti-skid decks all around -- currently they are only in a few places (presumably those most often stepped on).
He thinks there is too much line joining the stay and shrouds to the chainplates. He recommends using stainless chain to allow for shorter line and hence less stretching. He reckons it will be difficult to get enough tension in the rig without this change.
The CQR anchor has worked its hole and can move a lot in any direction -- it should be repaired.
The short lines holding the halyard purchases at the top of the mast [currently as per plans] should be chaffe-protected with rubber hose.

Some random notes and recommendations:

When anchoring, I need to be careful to make the XXX short enough that the rope doesn't chafe against the keel. I should also protect it from chaffing against the headstay XXX.
To ensure a joint of two plywood plates is as strong as the wood itself, fillet with a diameter of 10 times the plate thickness.
You can't put too much tension on the rig using your hands.
To remove stain from stainless (!) just use bleach.
The mast is made of scots pine ("casquinha") -- it is not a particularly durable wood, so I should watch out.
A drifter will probably be better than a spi on this boat.
Experiment with barberhaul on the genoa sheet, as the rail may be placed too far from the centerline.

We also tested all electrical and electronic equipment (using a borrowed car battery). Everything worked flawlessly.

The owner-builder agreed to make the necessary fixes (both the ones identified by the surveyor and the ones we had listed on my first visit) if I accepted to bear the materials costs (which I reckon will not be huge), so we did all the paperwork and the sale was closed. I felt very happy, but somehow burdened... feeling as if I had taken an elephant as a pet, so to say.

Over the following two days we improved the mooring by digging an anchor into the mud and replacing damaged ropes with new ones and also reglassed the stern. I also prepared a long TO-DO list for maintenance, fixes, improvements, and purchases:

Mantenimiento y reparación	Papeleo	Mejoras antes de salir hacia el sur	Comfort	Otros
Amarrar bien para el invierno	Registro	Quitar los candelabros	Nevera	Ancla moderna
Reparar el mascarón de proa de babor	Seguro	Resolver la sujeción del auxiliar (simple)	Tanque de aguas negras	Detector de gas en la cocina
Matar las avispas y quitar el nido de la viga	Licencia de estación de radio	Instalar líneas de vida	Ducha en cubierta	5m de cadena para el ancla de popa
Reparar la fibra despegada de la cabina delantera de babor	Impuestos (Portugal/España)	Comprar EPIRB	Sombra en cubierta navegando	Cabo de sobras para:
Reparar e instalar el aerogenerador	Baja del registro Portugués	Comprar linterna y baterías selladas	Sombra en cubierta no navegando	- Amarres
		Comprar VHF portátil	Caja para el motor	- Anclas
Lijar y pintar la verga		Comprar cuchillos de jarcia	Self-tailing winch	- Ataduras vigas
Lijar y pintar las cañas y travesaño del timón		Comprar chaleco c/. arnés y "tethers"		- Ataduras obenques y estais
Lijar y repintar pasamanos		Comprar pirotécnia
Lijar y repintar bloques de sujeción del piloto automático		Comprar o cargar extintores
Lijar y repintar tablilla de protección tras el piano		Comprar manta anti-incendios
Aplicar aceite a los estrados		Tensar la jarcia
Aplicar epoxy con protección UV a la escalera		Asegurar tensión y posición estay
Sustituir Sylkaflex escotillas en las que esté entrando agua		Equipo para subir al mástil
		Comprar cartas y Pilot Books
Reforzar por dentro los pies de los obenques que tengan más de 3cm de desviación		Jerrycans y embudo gasolina
Pintura en todos los descascarillados		Bocina
Frapping turns en los enlaces de las vigas		Bola y conos
Comprar e instalar baterías (90+90 Ah+)		Banderas N, C, Q, PT, SE, ES
Sustituir los tubos del gas si están caducados
Aplicar patente y anti-fouling en la obra viva

Rellenar los espacios entre vigas y apoyos (tras navegar)