So, splurging on a pool table, hot tub, and a telescope to enjoy the views would yield significant returns.I'd love to hear your thoughts!

Quote from @Zachary Deal: Choose neutral safe tones and get nice materials but don't splurge too much on very fancy cabinets, counters, appliances that someone else may not value the same as you.This is so true.

If the answer is yes, then it's a no brainer to make minimum payments on your 2.8% interest rate mortgage, and use the funds that you would have paid extra to pay it down faster, to either invest in more real estate, the market, or anywhere else where you can get a ROI > 2.8%.If the answer is no, then feel free to aggressively pay it down as fast as possible, to become debt-free faster, and just have a large amount of money in savings or to splurge with.The bottom line is that your 2.8% mortgage is GOOD debt.

I share more on splurging/saving for max ROI on my Bigger Pockets Episode (933:https://www.biggerpockets.com/blog/real-estate-933), if you haven't listened to it already.

Yeah, not trying to splurge there 

or should I splurge and get the higher end furniture i.e.

Most other costs are relatively standard I believe.  11) buy at market rates - dont splurge in a market because numbers look good - we are more than likely going to see balking in prices - if not a little recession in the next few years - would suck to own something you couldnt sell becuase you bought the most expensive property at the top - goes back to being mindful of your market.  

I would not splurge on your first home.

I would say this was the biggest splurge for this project.

I splurge for a full cable package here.