Wanting to use healthy fats but can i afford it?

Hi

I am on the low end of healthy weight and would like to maintain.

I live a moderate lifestyle working with kids all day and have regular light/mod exercise most days with light weight sessions 2-3 times per week.

I have a treat meal on Sat- it may be like 700-800 cals for the meal with like 50 percent fat. I would eat fruit and veges around it of the rest of the day.

I have been very reluctant to add any healthy fat to my cooking as I feel that on sat i have like 50g or so of fat.

During the week my diet is -I eat low fat cheese and skim milk and white meat and have like eggs 3 times. 

Could I afford to add a teapsoon or Table of canola oil to spoon to my dinner meals every night.

Can I maintain my weight with doing all of the above  taking into account my treat meal?

Welcome any advice PLEASE :)

You could. Personally I avoid oil, and instead opt for nuts and peanut butter to get fat. It just seems more redeeming to me than pouring a tablespoon of oil onto my food. It also provides some protein, whereas the oil is pure fat.