[Flabbibulin]

My opinion is to only go with a personal trainer if the cost is not an issue at all. If it is, I would suggest that you skip it and rely on personal discipline and a little research.

50lbs in 8 months is doable, but I am of the opinion that a goal like that will require you to count your calories. 1.5lbs a week is a fairly big caloric deficit, and assuming you want to do it without restorting to unsustainable techniques or dieting fads, you are going to have to get very active and very restrictive with your diet. I believe that weight loss is very possible on healthy and sustainable diets- certainly nothing sub 1500 for men. I did 50lbs in 6 months on between 1700-2000 calories a day.

Regardless of whether you go with a PT, I would suggest getting a macronutrient/calorie count app like Lose It. Learning to accurately count your calories in and measure them against BMR + exercise will be key imo. I would suggest that a caloric deficit of around 750 calories a day is doable- but probably only if you are committed to a good work out program.

I don't think counting calories is necessary for someone looking to just shed a few pounds and look better, but a fairly sizeable goal like 50lbs may require adding things up. Researching healthy dieting plans that fit your targeted caloric number would be a good idea.