Brewing smaller batches?

I've been brewing beer for about a year now and have made around 10 five gallon batches. My problem is I like to brew beer faster than I can drink it. I know what a horrible problem, but does anyone have experience with brewing 1-2 gallon batches. I would rather do that so I can brew and try more styles faster, then when I find/make a recipe I really like I will make a bigger batch. Would I need to down size my equipment in order to do this or could I still use my 10 gal mash tun, 15 gal brew pot, and 6.5 gal carboy?

Most people who do smaller batches use smaller equipment. A lot of small batch brewers brew those batches on the stove top, and usually use a smaller pot. 6.5 gallon fermenters are a little large imho for 2.5 gallon batches. I'm more confortable with a 5 gallon, though I usue 3 gallon fermenters for small batches. You can use any sized mash tun, but be aware that less in there can mean less heat held in the cooler during the mash.

How much water should you use for the mash if you are making a 2.5 gal batch and how much should you use to sparge?

Just like larger batches it's really determined by the boiloff rate during your boil. Traditionally it's a gallon to a gallon and a half per hour. Use brewing software to calculate how much of each based on that number

You might check with your local bakery or donut shop. Things like creme filling and frosting often come in 4 1/4 gal buckets with lids - you can just drill a hole for an airlock or blowoff tube. I scored one for free this way, it's a perfect size for fermenting 2.5 - 3 gal batches.

I brew 2.75-2.5 gal batches often. Perfect size imo for testing recipes. Allows for a lot of brew days. I use my 5 gal equipment also. I have a 5 and 10 gal pot, 6.5 and 3 gal fermenter, i use them both as i dont secondary or lager. I typically use just over 4 gal for 2.75 gal. You should google a mash/sparge calc and input your own data.

So imo use the same equip!