Need to repaint my house. Prep help, please.?

My house is 53 years old. Well-built with 105 lap board and brick. We purchased the home 12 years ago. The prior owner did not prep the wood before repainting. It is starting to bubble and chip.

We have removed and replaced the rotten boards. We are unsure what to do next. Scrape? We have been told to try sandblasting. Another friend said that would not get all of the paint off, and there would still be a lot of paint on the house. Sanding what is left by hand or with a palm sander would be a daunting task.

We are preparing to sell our home. Real estate in our area is doing well. Top dollar is received by those whose homes look the best, obviously. We want to have the surface look as good as possible before caulking, priming, and painting.

We can do the work. We do not need a painter. We would like to know the best method(s), equipment needed, and approximate time to complete.

Thanks.