I have 3/4 of an acre, mostly grass, with many large trees. When I used bags, I averaged around 200 large leaf bags each year. I would strongly suggest ditching the leaf vacuum, and consider one more solution, although much more expensive overall. This was something a friend recommended to me, after I struggled for an endless number of years dedicating over 200 hours on weekends solving the problem. I told him I was thinking of getting a leaf vacuum. He laughed at me and said I already had the riding mower, and it was much more efficient. He said he tried the leaf vacuum, but the bag is so large and unweildy when full. The bag also filled up with about the same amount of leaves as a bagging attachment for my mower could handle.
I perform this task completely by myself, and I expect that to continue for the next 10+ years.
Riding mower with bagging attachment and high-lift blades. At least a 42 inch mower deck.
Backpack leaf blower
Somewhere to dump the leaves, or a device that will hold the bag while you dump the contents of the bagger into the bag.
This is not a joke. My contractor was working on my house last fall. I told him I was going to mow up the leaves, and it should take me 1.5 to 2 hours. When I walked away, he told his employees that I was a moron. 90 minutes later I finished both the front and back yard. He stopped me at the end of his day, and told me that was the most amazing thing he had ever seen, and he apologized for what he admitted that he said behind my back. We got a good laugh.
Step 1 - Lower the blade deck to about 2.75 inches, at least that it was works for my mower. Mow the main part of the lawn. Keep an eye on the bags and immediately turn off the blades just as the bags are about full. You do not want to clog the tube, especially if the leaves are damp, and they always seem to be damp where I live. It took me a while to learn that I get about one trip down and back in my yard, and my bags are full. This sounds tedious, but it is incredibly efficient. I then dump the contents of the bags, and go another round. I do this over an over until the main part of the yard is empty.
Step 2 - Is to don the backpack blower, and blow all the leaves on the perimeter of the yard into the part you can mow. I have a fenced in back yard that I cannot mow the perimeter. Some people do not need to do this. The idea is to push the leaves from areas of the yard that they cannot ride the mower, into the open parts of the yard. Yo do not want to do this first. It is better to have low flat distribution instead of large piles. The mower struggles with large piles.
Step 3 - Resume mowing and dumping the bags until finished.
My biggest upgrade was getting my fence gates to be wide enough for my mower to pass through with the bagging attachments connected.
Every year I thank my friend that suggested this method. I have to do it three times a year, 6 hours versus 200 hours.
Of note, I do not bag my grass, I mulch it. I only use the bagger for leaf removal. There are also bagging attachment wagons that can be found online, that use the ducting and high lift blades, but are easily dumped versus the typical bagging attachment. I think Silver Cymbal on Youtube has demonstrated this method. I did not buy one, mostly because they are rather large. The cost of the bagger and the blower is about equal to having yard pros come 4 times where I live. That would last me two seasons.