i have used three different guns at work HF, eastwood, wagner. they all "work" but you get what you pay for. the HF loss a ton of powder on the floor cause it didn't stick. the eastwood was better in that respect. the wagner gun cost the most but is hands down great, not for the dyi guy too pricey
as for the oven, keep the peace don't walk into the house with a rack of parts to cook. at my work we started with a $18 goodwill stove then made our own. getting up to 380-400 is the most important.
Buy good paint. the paint you buy will be a big part of how it comes out and lasts. we use cardinal. don't buy hf unless you are practicing.