I also don't lease my heifers - too tempting for people to get them too fat and ruin them for life. I have let a few go with friends with the same conditions that DL mentioned, back in good shape (NOT TOO FAT) and bred.
When we started out, we've done it several ways. We just paid for everything & returned heifer- bred (they provided the semen). The owner paid for a % of the feed & heifer was also returned bred.
We did a venture one year w/ a young man. He showed the heifer & returned him & we gave him her first calf.