We hired a plumber (that we have used for years) to fix a tub spout leak and toilet repair.

Water heaters, furnace, plumbing leaks, replacing a roof, replacing the main water line, tree trimming, microwave replacement, etc. $20-25K would be awesome but you can likely get by depending on condition for $10-15K. 

So if the pipes are not leaking , they are fine .  

There is a new smoke detection unit that has been appearing on my facebook feed which also does noise detection and is being marketed towards STRs.

this is the most transparent scammer outthere, i am actually very worried about OP if they can't detect this easily, he is selling mortgage, oil, insulin and tax services in one hospital out of ohio somewhere...come on...

They are cheap and will save you from future leaks and clogs.

I have a house planning to replace pipe in crawlspace with PEX but concerned about mice chewing through it and causing a major leak.

And the time I spent writing the lease, screening the tenants myself, go over to the property if the kitchen sink is leaking?

house didn’t have any leak (as they say and as on disclosure form) house wasnt owned by professional investor, it’s owned by a couple who bought in 2017, completely fixed the rear unit and added 2 new bathroom in front, which they divorced around 2019/2020 based on my search, so I am somewhat thinking there not much to hide?  

I sure won't be popping up to fix a leak so property management will have to be in the budget.