Its very cheap to build your own incubator. If you use a good thermostat that will be the most expensive part. You can find older half size fridges/freezers for very cheap/free. You just need the shell, they don't have to work. Then you wire up your heat source inside, your thermostat, a little bit of ventilation(tiny bit) and you will have something that will out perform a havobator and hold many more clutches. My whole incubator probably cost $60 to build and recently added a better thermostat for about $80. I can probably hold in there 20 clutches of eggs at a time, more if I changed the shelving a bit.