The caulk will dry, shrink and leak over time.I have used window replacement companies with long track records and supplier warranties not the big box stores because the do it every day. 

I planned to spend no more than $1500 and to re-use the furniture for the next house.

We store ours with Corporation Services Company: https://www.cscfinancialonline.com/Home.aspx

You don’t necessarily need to have a full CapEx reserve stored up, but you need to have enough that if something major breaks (IE.

The location is great on a main thoroughfare next to big box stores and other high quality retail. 

To the original question- if your a "store it under your mattress" kind of investor then yes, having several rentals is probably too risky for you.

Oh and one more question,  on the HUD home store. what dose it mean when it says the bid is a Lottery ?

Welcome to BiggerPockets, @Antoine V.I used Home Depot store credit cards to fund my flips.

Furniture, kitchen utensils, flat screen televisions, music recording equipment, a lot!

I'm assuming the post office but I know the private post offices and grocery stores sell them too.