2009 Kubota RTV 900, 2009 Kubota B26 TLB & 2010 model LS P7010
My old wheelbarrow is over 20 years old and the original tire would never stay aired up. I finally bought a new tire and rim at Lowes for I think about $12 but that was over 5 years ago. I haven't used it much since then, mostly it just leans against the wall of my shop, but the tire is still aired up and I haven't put any air in it since I got it.
My wheelbarrow came with a tube in the tire, but it still didn't like holding air. I put some liquid laundry starch in it. Liquid laundry starch does the same thing as slime, but costs about $2 a quart. Works great, I put it in the tires on my riding mower too.