Is there a way to exclude specific transactions from being captured/included in Budgeting reports?

For example I use a CPAP. I have a category for all things related specifically to the CPAP. I mainly want to use this budgeting category for tracking the regular supplies I need to purchase. I did recently just start this "treatment" and purchased the machine itself... I don't really want the machine calculated into my averages and such when I am in the budget section... Is there a way to exclude just the machine transaction from that category when looking at the budget? For example when I look at this category line on my budget the calculated average spending is going to be, let's say, $100 per month with the machine purchase included. Whereas the actual monthly average spending will be ~$20 or so on filters or replacement parts (totally making numbers up here). I don't anticipate buying a new machine all that often, so I don't really want to try and include that cost over 60 months or so and have the category roll over that amount... Does that make sense?

My first thought was to try and have a tag ("NoBudget" for example) that I might be able to have the reporting/budgeting overlook... I couldn't easily see a way to configure that though... so my wondering if there is another way to do something like this.