how do I account for a purchase of fractional ownership in real estate

[Mike9241]

if this is rental real estate, multiple owners probably require filing a partnership return so each owner properly reports their share of any profit or loss. failure to file such a return, if required, can result in substantial penalties.

if this is not rental real estate, then each owner might need to report their share of expenses - likely only mortgage interest and real estate taxes - on schedule A.