Unintentionally swallowing blood

Q: If one felt the taste of blood in the mouth and eventually so he went to bathroom and spat out and there was discoloured saliva and didn’t seem to see blood and swallowed intentionally as he didn’t think there was blood but it tasted like blood. So most likely he would have consumed blood but not intentionally. Does this mean his salah may not be accepted for 40 days because of consuming this blood?

Nikaah without witnesses

Q: If a boy texts message a girl saying, "Do you accept me in nikkah" and the girl texts back,"yes" and then the boy texts, "same here", and during this there is no witness on the girl's side but the girl does not know if there were witnesses on the boy's side or not. Is the nikaah valid?

Suspending the talaaq

Q: I issued my wife with a verbal talaaq in my fit of anger and my negligence unfortunately. I know that's gone though. 

I then issued 2 suspended talaq as follows: 

1) If she tells anyone in my family or her family about our marital issues and problems then she will be divorced. 

2) If she drives a vehicle she will be divorced. 

Is it possible for me to revoke these suspended talaaqs? 

Is it possible to revoke these suspended talaaqs before the event takes place? 

Is it possible to revoke these suspended talaaqs after the event takes place? 

On another occasion I told my wife the following: "If you not back by 2pm I will divorce you" but I didn't divorce her. It was a threat. Is this counted as a talaaq?

Fardh ghusal for a person who has a medical device taped to his skin

Q: There is a device on the market which is attached to the skin. It gives you a continuous and real time reading of your blood sugar levels by which a diabetes patient will know when to take his insulin and how much insulin he should take. (Not over or under administering the medication) 

The device is quite expensive (removing & changing the device each time you require a farz ghusal will be very costly). The device has an adhesive tape by which it is attached to the skin thus preventing water from reaching underneath it. Will the farz ghusal of a person wearing such a device be valid if he makes masah only over the device and washes the rest of the body?

Selling an unclaimed collateral to retrieve one's money

Q: A year ago, I had a customer who wished to purchase an item for R1200. He only had R800. So he opted to leave his spare wheel with me. I told him that if you don’t come, I’m going to sell your spare wheel, he said yes, no problem, but I’m going to come. 

It’s been a year; I can’t get hold of him and he hasn’t come back. The spare wheel is worth about R2000. What should I do? Should I sell the spare wheel for R2000, take my R400 and give the remainder in Sadaqah, or should I sell it for R400?