>>4436773Mirrorless is easily the most compact, but if you want small form factor and low price, you'll probably end up with an APS-C. There are plenty around from Canon, Sony and Nikon, so take a look at those and narrow them down to APS-C and your budget, then do research on which model sounds or looks right to you.
A word of advice too is don't worry about gearfags and brand loyalty shit, buy whatever you want to buy and ignore tards that bitch about brands.