Sprinkling water over impurity to purify it

Q: In my pregnancy I've been getting clear or yellow discharge very rugularly.

So sometimes if I'm out and I have slightly more than a Dirham size then I just sprinkle water over it and try to scrape it a bit but it's always wet, not dry. So sometimes I can't wash and change my underwear when I'm out.

Does sprinkling water over suffice?

It worries me because of my wudhu and salaah and it's validity.

Supplier putting a condition that a sale cannot be cancelled once an item is ordered

Q: My supplier sends me pictures and specifications of items that he is selling via WhatsApp. Whatever items I want, I order via WhatsApp. Is it permissible for my supplier to put a condition that once I order an item, the order cannot be cancelled, or is stipulating such a condition zulm (oppression and extortion)?

Sale of a Person in Financial Constraints

Q: What is the ruling of Shari’ah in regard to a person who is in financial constraints and people (e.g. his creditors) take advantage of his situation? They are well aware that due to his situation, if they offer him an extremely low price for his goods, he will accept due to his desperation and sell it to them. An item worth R50 will easily be sold to them for R5. Is it permissible for them to ‘squeeze’ him in this manner, due to which they will get much more money from him than he actually owes them?