Check

Supported Methods	Supported Parameters
GET, POST, PATCH	Id, number, page, pageSize, modTimeStart, modTimeEnd, isDeleted

{
	"ID": "",
	"ToBePrinted": true,
	"Account": {
		"ID": "",
		"FullName": ""
	},
	"PayeeEntity": {
		"ID": "",
		"FullName": ""
	},
	"Address": {
		"Line1": "",
		"Line2": "",
		"Line3": "",
		"Line4": "",
		"Line5": "",
		"City": "",
		"State": "",
		"PostalCode": "",
		"Country": "",
		"Note": ""
	},
	"Date": "2021-06-04T20:17:13Z",
	"Number": "",
	"Memo": "",
	"Amount": 0.0,
	"ItemLines": [{
		"Item": {
			"ID": "",
			"FullName": ""
		},
		"Description": "",
		"Quantity": 0.0,
		"Cost": 0.0,
		"Amount": 0.0,
		"Customer": {
			"ID": "",
			"FullName": ""
		},
		"IsBillable": "",
		"Class": {
			"ID": "",
			"FullName": ""
		},
		"ID": ""
	}],
	"AccountLines": [{
		"Account": {
			"ID": "",
			"FullName": ""
		},
		"Amount": 0.0,
		"Memo": "",
		"Customer": {
			"ID": "",
			"FullName": ""
		},
		"IsBillable": "",
		"Class": {
			"ID": "",
			"FullName": ""
		},
		"ID": ""
	}],
	"ExchangeRate": 0.0,
	"LinkedTransactions": [{
		"ID": "",
		"Amount": 0.0,
		"Type": "",
		"Date": "2021-06-04T20:17:13Z",
		"Number": ""
	}],
	"LastModifiedDate": "2021-06-04T20:17:13Z",
	"DeletedDate": "2021-06-04T20:17:13Z",
	"AmountInHomeCurrency": 0.0,
	"Currency": {
		"ID": "",
		"FullName": ""
	}
}

Important Notes

QuickBooks Desktop

When POSTing a Check to QuickBooks:

If you are not including a customer when sending in a check, you will need to omit IsBillable.
If you are sending in a customer, IsBillable must be set to true or false.