Reddit mentions of AmazonBasics Deluxe Microfiber Car Wash Mitt

One other thing - I would do a hand wash versus a pressure wash only. I love self-service car washes for maintenance but they don't remove stuck-on dirt and grime that you'd want off before claying or applying sealant. Also ONR assumes the use of a wash medium like a wash mitt. If resources are an issue I'd just pick up a cheap MF wash mitt, a $4 bucket from Home Depot, and maybe a grit guard.That + ONR should be plenty. If your self-service car wash won't bother you about bucket use I just put in $1 and go straight to pressure soap to blast most of the dirt, then fill the bucket with water + ONR and dry with a MF towel. I'd also try to do as much as I can in one place since the drive home would introduce a bit of new dirt.

If this seems like too much of a hassle, I'd say just hand-wash with ONRWW + MF towel-dry at the car wash and you're set and waxed with protection until you can find a place to do a hand wash, dry, and seal in one place. I do it in my apartment's stacked garage, personally.

Chapin pump sprayer from Walmart is $5. ONR is $55 for one gallon on amazon (wash+wax instead of just wash), which is good for ~200 washes (more or less depending on your dilution and use). Big microfiber towels are $6 for 3 on AmazonBasics. The mitt for washing on AmazonBasics is $5ish. China washing mitts are too small for European hands, but they are less than $1 each. I went with AmazonBasics for the mitt. Grit guard from china is ~$6 each -- get the smaller diameter, 23cm vs 26cm, one so you know it fits for sure. Get buckets from Lowes or Home Depot for $5 each. When you read China, read 30 days for shipping.

If you experience bird poop or something like that, like salt or big bugs, go to a self-service car wash where you can power wash off the crap before ONR. Or just do a touchess carwash before ONR for about $7 a wash, which is the most basic wash at my local touchess carwash.