No brewing for me over the weekend. Had to get the house ready for an inspection on Wednesday. Besides, I have a lager in the fermenter that'll be in there for the next 3 weeks or so, so no real urgency. I'll probably do one this week or next week though.
I did buy one from ebay and it was not expensive less then 30$. After I got it I found that it had to be calibrated for wort because of color they were meant for clear sugar solutions hence the main scale is in BRIX and it has a secondary scale SpGr. So to solve the calibration problem I found this Refractometer Calculator and link: https://www.brewersfriend.com/refractometer-calculator/ as you read it, it leads to this link that requires you to enter the SpGr for a sample and the corresponding Refractometer reading then it will calculate for you the correction factor for the unit you have purchased, Link: https://www.brewersfriend.com/how-to-determine-your-refractometers-wort-correction-factor/
I find it is quit handy I use it for the initial reading and then wait for the active fermentation to subside and take a reading with 3 drops and keep checking until there is no change for several days. As for the problem with an incorrectly reading Hydrometer the error should cancel its self.