SQL if statement in where clause for searching database

ALTER PROCEDURE spVillaGet
-- Add the parameters for the stored procedure here
@accomodationFK int = null,
@regionFK int = null,
@arrivalDate datetime,
@numberOfNights int,
@sleeps int = null,
@priceFloor money = null,
@priceCeil money = null
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;

-- Insert statements for procedure here
select tblVillas.*, tblWeeklyPrices.price from tblVillas
INNER JOIN tblWeeklyPrices on tblVillas.villaId = tblWeeklyPrices.villaFK
where
	If @accomodationFK <> null then
		accomodationTypeFK = @accomodationFK
	 @regionFK <> null Then
		And regionFK = @regionFK
	IF @sleeps <> null Then
		And sleeps = @sleeps
	IF @priceFloor <> null Then
		And price >= @priceFloor And price <= @priceCeil


END

select tblVillas.*, tblWeeklyPrices.price
from tblVillas
INNER JOIN tblWeeklyPrices on tblVillas.villaId = tblWeeklyPrices.villaFK
where (@accomodationFK IS null OR accomodationTypeFK = @accomodationFK)
  AND (@regionFK IS null or regionFK = @regionFK)
  AND (@sleeps IS null OR sleeps = @sleeps)
  AND (@priceFloor IS null OR (price BETWEEN @priceFloor And @priceCeil))

SELECT *
FROM  vehicles
WHERE ([vin]   LIKE COALESCE(@vin, [vin])     + '%' ESCAPE '')
  AND ([year]  LIKE COALESCE(@year, [year])   + '%' ESCAPE '')
  AND ([make]  LIKE COALESCE(@make, [make])   + '%' ESCAPE '')
  AND ([model] LIKE COALESCE(@model, [model]) + '%' ESCAPE '')

SELECT *
FROM  vehicles
WHERE (([vin]   LIKE COALESCE(@vin, [vin])     + '%' ESCAPE '')
       OR (@vin IS NULL AND [vin] IS NULL))
  AND (([year]  LIKE COALESCE(@year, [year])   + '%' ESCAPE '')
       OR (@year IS NULL AND [year] IS NULL))
  AND (([make]  LIKE COALESCE(@make, [make])   + '%' ESCAPE '')
       OR (@make IS NULL AND [make] IS NULL))
  AND (([model] LIKE COALESCE(@model, [model]) + '%' ESCAPE '')
       OR (@model IS NULL AND [model] IS NULL))

Where accomodationTypeFK = IsNull(@accomodationFK, accomodationTypeFK)
    And regionFK = Coalesce(@regionFK,regionFK)
    And sleeps = IsNull(@sleeps,sleeps )
    And price Between IsNull(@priceFloor, Price) And IsNull(priceCeil, Price)