What is the fastest used car under $25k?

https://www.buyingadvice.com/5best-used-cars/5best...

Go back far enough (old enough, high enough mileage)

and you can easily find one that matches your budget.

The mini cooper s is really fast car and is under 25k.

A mustang or camaro

Subaru WRX STi preferably one with a 2 litre engine, more reliable than the 2.5l.

Maybe not the highest top speed, ( which you can’t use on the street. Virtually every modern car can do 100mph but driving at that speed on the street will land you in jail) but one of the best for acceleration , which you can actually use.

Add in AWD for safety ( watch YouTube for idiots in high powered RWD cars losing the back end even on dry roads), four seats you can use as the family car and you have everything you need. 

Price insurance before you buy. Anything fast is going to cost an arm & a leg insurance wise.

Camaro.                         

If you want fast and cheap, you want a 600cc sport motorcycle.

Fast on the streets is STUPID.