Rapeseed is sold as canola oil in North America. If it’s hot it shouldn’t be an issue. Most of the issue comes from the necessity to heat the oil to the appropriate temp. Give it a try, but is it really cheaper? A gallon of canola oil on Walmart+ is $7.48. This price makes sense in Europe and the UK where diesel comes out to $9.xx per gallon.
If you’re trying to save money over time, WVO and a preheat and/or dual tank system are a better route. You can build a filter and storage system very cheap and get the oil free. I don’t know how much a dual tank system would cost.
The cheapest would be filter the WVO then blend it with diesel. Figure out the best ratio you can run and adjust as temps change.