I mount and balance tires myself. Save a bit of cash that way.
I buy my tires online. Ebay usually. I usually know what brand and model of tire I want. I then put that and the tire size I want in the search engine.
A long list comes up. There is a pull down box where you can choose how you want items listed. Click the cheapest with shipping.
Now they are listed cheapest first. You want to skip over the used tires. Then check the first one you come to. You may even find them in sets, both a front and rear for a cheaper price.
You may find the tires you want several sellers list them, Some ask as much as if buying local. Others much less.
If I have the rear tire on my Harley done at the shop, as in ride the bike up have it done and they charge almost $300.
I can buy the same tire for $125 online, tube around $15.
I have always gotten good tires this way. Seldom over a few months old.
I get tubes and rim strips the same way.
Often the rim strips are ok. Mostly want to replace if torn or hole worn through.
Sometimes I reuse a tube. Depends if I feel too cheap. Usually I pinch or tear them getting the tire off.
I try to keep an extra tube in the sizes I need on hand. Never can tell when you will pinch one mounting a tire.
Leo