a peddal boat on a pond.

+1.

With BRE colors?

If you really want to know what cars are good cheap racers, I suggest reading a couple issues of Grassroots Motorsports. They always feature some junker they've built into a competent track car.

Owning all of a '90 Mazda Miata and 911 and a 930 I'd say go with a high mileage well taken care of 911. That is the most bang for your buck! Yes a Miata is cheaper and parts are cheaper but I think in the long run you'd have way more fun in a dialed in 911 old or new than a Miata. Off the track you'll be WAY more relaxed with a 911 over a Miata is you get my drift...... ;)

A non-turbo RX-7 with a good suspension and fresh engine will give you many many years of problem free track days.
I have a friend with a ITS RX-7 and his engine is on its 8th season. Yes EIGHT years and never been opened. He runs at the front of the herd too.

The best part with ANY Mazda? Mazdaspeed!! Prove you race in 2 events a year and get better prices on parts than the mechanic at the dealership can get. Dont want to track race only want to do DE's? No problem do 2 Autocrosses and your set for the year.

DO NOT get a turbo, trust me on this one. Although the power a well sorted turbo RX-7 makes is mind bending especially when you consider its a little 1.3 liter engine.

IMHO, there is no less expensive track car than a 911.. For the most part, prepping one for track means taking things off; not adding or substituting things. You'll want a sway bar setup, yes, but you can run on stock brakes if you have a stock(ish) engine.

Early 911s are thoroughly over-engineered. I've had a few as track cars and between sessions, I could relax, nap, read a book; whatever, while other folks in my run group were feverishly fixing or adjusting parts.