I've done my own painting, interior and exterior, for 30 years. I have only used SW products and have had great success. In fact, I use so much, I'm in their system to get the Contractor discount, so I pay 40% less than list. Good paint costs money, there are no bargains. For exterior and interior I have used SW SuperPaint at $60/gal and it has lasted 20 years. I've lately switched to Duration at $80/gal (mainly for trim, my current house is hard coat stucco). Both are 100% acrylic latex paints. SW runs occasional sales, so you could get these at 40% off or pester them and buy alot, they may give you the Contractor discount if you deal with the manager. Hit or miss on quality of personnel in these stores, but some guys are absolutely fantastic, worth their weight in gold if you find one. Go to another store if the people you are dealing with are half-assed, they are out there. SuperPaint is a great product, been around a long time and is good enough. Their exterior latex primer is what I would use over both oil or latex old coats. A-100 alkyd primer, if you are priming bare wood only or exposing bare spots, is a great product, but otherwise, the A-100 is an inferior "Contractor Grade" paint line for house builders and such not concerned with longevity. Stay away from it. For your stucco, I can't help with the paint, but I just resurfaced my house with Acrocrete Acrotex at about $3/SF. The house looks new. I had some deterioration and cracking issues and I could not be more pleased. Been on there for 3 years now and gets hit with some severe conditions in areas. I hired a Contractor for this, an acrylic cementitious base is trowelled onto all surfaces (Acrobase 60) to end up smooth and a fiber mesh is imbedded to span any potential cracking. Once dried, the Acrotex finish is applied with the finish pattern of your choice. This is an all acrylic system, ends up about 1/10" thick on the existing stucco. Fantastic alternative to painting, you can change the color and the swirl pattern, solves issues if you have them. The only problem is finding a good installer, there is a workmanship aspect that makes it a bit trickier than painting. An old house like this, where alot of scraping is needed, is a prime candidate for the new PVA coating restoration systems like Zinnser Peel Stop. You basically scrape off the loose material and brush it on. It can be rolled or sprayed, but the brush gets in there good. It is fairly inexpensive (it is basically watered down glue) and works like gangbusters to hold everything back to the surface. You then prime and paint as usual over it. It is a surface treatment. You will not end up with a smooth surface, but cuts the scraping work by 90%. There are several products out there and they are of varying viscocities, you can do some testing with them to see which one works best on your surface. The Peel Stop is thinner than paint and it gave good results for me, I was painting over oil primed cedar shakes with 4 or 5 coats of deteriorating paint and I would not do that job any different. One last word about working on ladders, determine how long you can work before getting too fatigued, set a timer, and quit when the time is up. Accidents happen when you are fatigued and there is a tendency to keep going beyond ones limitations if you don't do this type of work often.