where are you located? the advice most often given to this question is to visit a sponsor and try out a couple or a few machines to see what you like.
Youd probably get away with a single boiler machine but Id stretch that bit extra for a HX. A well configured HX should give you excellent results and there are a few options around $2k. The only dual boilers Im aware of are the Expobar (that you dont seem keen on) or the Izzo machine that will be outside your quoted budget...
Just resist the temptation to bypass the sponsors for what looks like a better deal from somewhere else. The time spent configuring the machine properly is worth much more than a small saving you could make buying off someone who doesnt care as much.