I'm heading back home and need to paint one of the metal buildings on the farm, about 900 sq ft total. It's that rippled metal and has had white paint on it for almost 40 yrs. Last time it was painted was about 15 yrs ago. Not sure if oil-based or latex was used at last painting. (Has held very well: no yellowing, no chalking, some minimal flaking, some fade and there's some rust, mostly on shadiest side, hence the paint job). I will have about 10 days to work, weather permitting, found out I have a bit of tendonitis in my elbow, so am trying to take away as much labor time as possible but still do a good job with longevity. No color change, keeping it white. Shape of metal looks like this, and is basically siding on this building:

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I was going to prime and recoat with two coats of latex.

My prep questions:

Cleaning: I was going to pressure washer but there is wood trim at the eaves and trim. Don't want to soak the wood parts (this trip won't allow ample dry time) so thought I could just pressure wash metal siding only. It's not exceptionally dirty, just that darned rust. So perhaps a Soilax + bleach mixture would be ample on the metal, and just scrape the wood?

Rust: Will pressure washing remove rust? Or do I need to scrape/wire brush/sand those areas? (a couple small light patches, but largest area, about 25 sq feet, is very rusty.) Tricky wire brushing and scraping all those grooves. Then I read about rust conversion coatings. Is that a better option? (Tried to ask a guy at HDepot the other day about that, he had no clue what I was talking about.)

Primer: Need a good primer for rust. I read about 'red oxide primer'. Would that be a better choice? Any brands recommended? If rust conversion coating is recommended, they recommend priming as well. Does red oxide primer eliminate need for rust conversion coat? I can get most any atypical products around here and conveniently, lots of independent dealers but they're not used to rural projects. Near the farm I have to drive for products, but have access to farm supply stores (items for pole buildings), Ace, and a SW and BM store. So I might have to transport product(s) with me.

Top coats application: I was going to spray on with a sprayer to save time, but think I've hit a hitch. We have a little Wagner HPLV sprayer for our cedar fence stain. Helped speed the job. Now I see that sprayer probably won't handle latex products. So I'd have to buy another sprayer and haul it down there with me. Have looked at a couple Wagner with ho-hum enthusiasm and Graycos. (Can justify a decent sprayer as I can use it on rental properties too, unless those are more of a nightmare than they're worth for interior work.) So on the metal, should I just do a brush and roll? I think that's going to drag the job out, but if spraying won't save time, I'll do it the old fashioned way. If I brush and roll, I thought a large nap roller due to it being metal, but that would skip all the grooves in the metal.

Top coat product: most important, any recommendations for a quality topcoat product for metal would be appreciated. I cherish my time there and would rather be fishin' or 4 wheelin' so don't want to have to do this again anytime soon. ;)

Feel like I'm forgetting something and have to hustle to get this planned.

Faron/Michael/Paintguy, don't see you much here lately (everyone is well and enjoying summer, I hope?).

Any and all input appreciated!