One thing I'd like to add on this is saving up more money will pay off later. Here's the way I look at it. My first incubator was a little giant still air with an auto egg turner. Results were dismal. Total failure of 120 chukar eggs. The reason it would rise and fall quite a bit. For my first hatch I was constantly re-adjusting to compensate. Cooked the whole lot eventually. Later I learned that you need to set them low because they climb a lot higher than wanted. I started actually getting hatches, just with very low percentages. I bet there are plenty of folks on here that have mastered them and can tell you how to get the best success out of them. Mine was short lived and burnt up in the first season so not the best for giving advise with it. Definitely wouldn't buy another.
Next was a brower top hatch. Great concept but another poor incubator. Also a big variation in temp and cooked quite a few. Did manage to get 60% or so hatches though once I worked with it a bit. Thankfully I sold it because later I found out they were catching on fire and burning people's houses.
Next was a gqf,1588. Same design as the little giant styrofoam incubators, just with a digital thermostat and tiny fan. Hatch rate is generally in the upper 90% range. Once was 119 hatched and 1 didn't. Worth the money to save up extra for that model. It's the cheapest good one I know of.
Next were Dickey's and GQF cabinets. As good or better than the 1588, just more capacity. I bought all of them used on craigslist. Not exactly budget friendly but the most expensive one was $375 so not a huge chunk of money thrown away either.
I've never really had the patience but there are some very good designs of home built ones on this board. I would bet the recent cooler one would be as good or better than the factory cabinet models and I believe the price was pretty reasonable for parts.
