Making use of Comparewise to get quotes from different vetted lenders will allow you to compare repayment amounts and interest rates for your given budget.
It is also important to note that getting a variable-rate mortgage comes with lower introductory rates than a fixed-rate mortgage. However, obtaining a fixed-rate mortgage when the benchmark index interest rate is low, could be more beneficial in the long run.
Bear in mind too that there are first-time homebuyer programs that sometimes offer better rates. Putting in a bigger down payment will also play a part in reducing the rate.