If those are your favorite combos and you can't afford to jump into the designers, start with the bases for those morphs, like axanthic, spider, albino, pastel, or butter/lesser/mojave. Your cheapest ones are probably going to be pastel, spider, or mojave; just be aware that mojave X mojave BELs have a silver head--this can work both ways though. If you are partial to the silver-headed BELs, get mojaves, but if you want a cleaner BEL, stick to lessers or butters.