First off, I have a 25 year old aluminum boat I bought in Venezuela
about 6 years ago. I was left on the hard
for three years so visually it was in rough condition on the exterior but interior
was nice enough.
Aluminum doesn't rust, it corrodes usually in the form of pitting. Put your hand in the bilges and rub the bottom. If it feels sandy, it probably is some corrosion
especially if is a damp area. Dampness may not come from exterior leak but interior
such as refrigerator
box drain, anchor locker
drain area etc.
These can be cleaned up but should be checked carefully.
Are you fuel
and waste tank integral ie built into the hull from aluminum plate? Both systems have their advantages and disadvantages. The main advantage of integral is that the boat is double hulled in that area. Usually there is a "coffer" dam between the two tanks
which is nothing other than empty space so that even with amazing corrosion there would be no chance of fuel
getting into the water tanks
or vice versa.
Are your deck
fittings welded or bolted on? Again both methods have advantages and disadvantages. If bolted do you have easy access to the nuts below deck through the insulation
and shell ceiling material?
Which brings up another important point, make sure the boat is well insulated whether you are planning on northern latitudes or southern, a well insulated boat is very important.
From what I read in your survey report most of the items listed seem fairly minor or at least easily repairable if if a few good swear words might be needed to accomplish the tasks