Complex SQL Query using AVG and count

I am looking for some help with two queries using the following table/data. It would be great to see the most efficient way to achieve these.

Queries

1: Show all homes with rent above the average rent value for their Company

2: Show the number of homes registered 0-3 months, 4-6 months, 6-12 months, 1- 2 years, and 2+ years ago

Thank you for looking.

CREATE SCHEMA homes;

GO

CREATE TABLE homes.Companies (CompanyId INT, CompanyName NVARCHAR(50));

INSERT INTO homes.Companies VALUES
 (1,'Company A')
,(2,'Company B')
,(3,'Company C')
,(4,'Company D')

CREATE TABLE homes.Branches(BranchId INT, CompanyId INT, BranchName NVARCHAR(20));
INSERT INTO homes.Branches VALUES
 (1,1,'Liverpool')
,(2,1,'Blackpool')
,(3,1,'Stockport')
,(4,2,'Durham')
,(5,2,'Oxford')
,(6,2,'Cambridge')
,(7,2,'Manchester')
,(8,3,'Newcastle')
,(9,3,'Hull')
,(10,3,'York')
,(11,4,'Birmingham')
,(12,4,'Stoke on Trent')


-- DROP TABLE homes.Properties;
CREATE TABLE homes.Properties (PropertyId INT, BranchId INT, Address NVARCHAR(200), Rent INT, RegisteredOn DATETIME);
INSERT INTO homes.Properties VALUES
 (1,1,'12a, Station Street, Liverpool',500,CAST('2019-12-31' AS DATETIME))
,(2,1,'12c, Station Street, Liverpool',475,CAST('2021-06-15' AS DATETIME))
,(3,3,'39, Main Road, Stockport',410,CAST('2022-09-30' AS DATETIME))
,(4,3,'12, Dovetrees, Manchester',700,CAST('2022-08-19' AS DATETIME))
,(5,5,'16, St Giles, Oxford',825,CAST('2023-02-28' AS DATETIME))
,(6,5,'32, George Street, Oxford',1100,CAST('2022-04-01' AS DATETIME))
,(7,5,'16, Main Road, Eynsham',680,CAST('2021-03-24' AS DATETIME))
,(8,6,'3b, University Road, Cambridge',960,CAST('2022-01-14' AS DATETIME))
,(9,7,'98, Heaton Road, Manchester',795,CAST('2022-09-07' AS DATETIME))
,(10,8,'64, St James Park, Newcastle',550,CAST('2022-11-26' AS DATETIME))
,(11,8,'47, St James Park, Newcastle',630,CAST('2023-01-16' AS DATETIME))
,(12,10,'6b, Station Lane, York',520,CAST('2022-07-19' AS DATETIME))
,(13,10,'24, Newcastle Road, York',510,CAST('2022-03-15' AS DATETIME))
,(14,11,'64, Bull Ring, Birmingham',1025,CAST('2022-12-03' AS DATETIME))
,(15,12,'Willowmead, Pottery Lane, Stoke on Trent',765,CAST('2022-05-12' AS DATETIME))

1. To show all homes with rent above the average rent value for their
   Company :

SELECT p.PropertyId, b.BranchName, p.Address, p.Rent
FROM homes.Properties p
JOIN homes.Branches b ON p.BranchId = b.BranchId
JOIN (
    SELECT c.CompanyId, AVG(p.Rent) AS AvgRent
    FROM homes.Properties p
    JOIN homes.Branches b ON p.BranchId = b.BranchId
    JOIN homes.Companies c ON b.CompanyId = c.CompanyId
    GROUP BY c.CompanyId
) AS subquery ON b.CompanyId = subquery.CompanyId
WHERE p.Rent > subquery.AvgRent;

The query above joins the Properties table with the Branches table and then joins with a subquery which calculates the average rent per company.
It selects only the properties where the rent is above the average rent for their company.

2. To show the number of homes registered 0-3 months, 4-6 months, 6-12
   months, 1-2 years, and 2+ years ago

SELECT
    CASE
        WHEN DATEDIFF(MONTH, p.RegisteredOn, GETDATE()) <= 3 THEN '0-3 months'
        WHEN DATEDIFF(MONTH, p.RegisteredOn, GETDATE()) <= 6 THEN '4-6 months'
        WHEN DATEDIFF(MONTH, p.RegisteredOn, GETDATE()) <= 12 THEN '6-12 months'
        WHEN DATEDIFF(YEAR, p.RegisteredOn, GETDATE()) <= 2 THEN '1-2 years'
        ELSE '2+ years'
    END AS TimeRange,
    COUNT(*) AS HomeCount
FROM homes.Properties p
GROUP BY
    CASE
        WHEN DATEDIFF(MONTH, p.RegisteredOn, GETDATE()) <= 3 THEN '0-3 months'
        WHEN DATEDIFF(MONTH, p.RegisteredOn, GETDATE()) <= 6 THEN '4-6 months'
        WHEN DATEDIFF(MONTH, p.RegisteredOn, GETDATE()) <= 12 THEN '6-12 months'
        WHEN DATEDIFF(YEAR, p.RegisteredOn, GETDATE()) <= 2 THEN '1-2 years'
        ELSE '2+ years'
    END;

The use of DATEDIFF function is to calculate the difference in months/years between the RegisteredOn date of each property and the current date GETDATE(). Then, it groups the properties based on the calculated time range and counts the number of properties in each range.