I'm currently shopping for a mill and plan on sawing come early spring, and have the same questions as yourself.
Right now I have my heart set on the Woodland Mills HM 130 Trekker XL (delivered for around $7,000CDN). It looks like a great portable mill and isn't too heavy to pull. If I lived int he USA I would strongly consider the EZ Boardwalk 40 as others have mentioned due to the wide-throat and large log capacity.
I find the value in the Woodland Mills products to be quite good for a small-timer like myself. (30" capacity, 14hp, 22" boards, great reviews/customer service)
If business picks up however and I need an upgrade, without question i would buy the Wood Mizer LT15 Wide. (closer t0 $13,000CDN)