Before making statements about the US Constitution, I suggest reading it. The original Constitution said nothing about who does or who does not have the right to vote.
Voting standards during the colonial and immediate post-colonial period were the same as those in Britain, which operated on a simple principle: whoever paid taxes was entitled to a single vote, regardless of the amount of taxes they paid. When you paid taxes your name was enrolled on a list of tax-paying citizens and this list was used to control who was admitted to the polling station.
The laws pertaining to polling were all local laws, not constitutional matters and originally it was held that making laws concerning the right to vote were a state power.
The exclusion of, for example, women to polling places was a matter of decorum, not right to vote, and woman, indians, minors and other such people not allowed into a polling place, had every right to vote so long as they paid taxes. In such cases the property owner (ie tax payer) would send an agent or representative to vote for them and execute their will. For example, to quote the laws of New Jersey in 1800:
"... to and for the guardians of minors, and to and for the agents of
single women, or other persons, who cannot attend the meeting of the
owners and possessors, such agents being appointed in writing, to vote
at said meetings."
From the above law, you can see only single women were not allowed into the polling place and required an agent. A married woman or widow who owned property would presumably have been allowed to enter and vote herself.
As for enumerating the number of people entitled to vote you need only refer to a census from the period, such as the 1791 census. In those days the census focused on recording the number of taxpayers, not the total number of persons, so you will find counts of such persons, who are perforce voters in that census and can compare it to modern estimates of the total population to gauge the percentage of people entitled to vote.
As for how owners were identified, it depended on the place. In a small town or country the poll would be occupied by people who knew and could identify by sight all the property owners in town. If there was some question, the person would bring his deed. A person possessing a deed would be presumed to be the person named on the deed. In many places, especially large cities, when you paid taxes on your property you were given a receipt. This receipt gave you admittance to the polls. If you were a kid, an Indian or a woman, you would find a lawyer or other respectable person you trusted, give them the receipt and they would vote for you.