Sarnia-Lambton's real estate market continued its upward trend for the year in April.A total of 144 homes were sold, valued at $76.3 million. That's a jump from March when 120 homes changed hands, totalling $63.6 million.The average sale price is holding steady at around $530,000.Sales were down 15.8 per cent compared to last April while dollar volume fell nearly 19 per cent over the same period.Sarnia Lambton Association of Realtors President J…