(1) Usually a weak battery
(2) Probable the Power Seat regulator under the dash. It is plug and play. Use the search function and you will find specifics.
(3) Your AC probably need charging.
(4) Those bulkheads are almost impossible to find. I would use some good plastic epoxy. You could also try parts for sale on this site.

Good luck, almost any information is available here with the search function at the top of the page.