How are the 10 financed properties counted for married couple

[Eric Z.]

I’ve talked to many lenders, so far I have 3 different versions of about this 10 financed property rule.

version 1

10 financed properties per person as long as one person take the loan on each purchase. Couple can hold the title together

version 2

10 financed properties per person, but only one person can be on the loan and the title on each purchase.

version 3

10 financed properties per couple if you file tax return together. The lenders look at the tax returns.

which one is true here? or does different lenders count the 10 differently?