[{_id:1,status:"unpaid",subtotal:5000,total:4750,fees:250},{_id:2,status:"received",subtotal:5000,total:4750,fees:250},{_id:3,status:"paidout",subtotal:5000,total:4750,fees:250},{_id:4,status:"paidout",subtotal:5000,total:4750,fees:250},{_id:5,status:"unpaid",subtotal:5000,total:4750,fees:250}]

db.collection.aggregate([{$group:{_id:"$status",totalAmount:{$sum:{$cond:[{$eq:["$status","paidout"]},"$subtotal","$total"]}},latestDoc:{$last:{$cond:[{$eq:["$status","paidout"]},"$$ROOT","$$REMOVE"]}}}},{$addFields:{latestDoc:{$ifNull:["$latestDoc","$$REMOVE"]}}}])