Making a vow in one's heart

Q:

1. I made an intention that if there is a certain outcome I will give money in Sadaqah, the outcome occurred, is it permissible to use the money to pay for the postage of clothes parcel to relatives in India?

2. If it isn't permissible where can I give the Sadaqah money (what can the Sadaqah money be used for)?

Not revealing one's suppliers to others

Q: I am a work from home Muslimah and have a very small business. I have a few other ladies selling for me. My profit per item is half or sometimes less then half of what I pay per item. (To be honest I make R10 profit per item) so the person selling can also add a small profit or I pay them a certain percentage on sales made. Some people selling for me asked me where they can buy this items to sell for themselves. Is it wrong of me not to tell them cause knowing and believing that Allah Ta'ala gives rizik? I also feel burdened not telling them.

Adding the condition "goods belong to the seller until paid for" in a sale

Q: Please advise on below:

1. Many companies state at the bottom of their invoice "goods remain the property of the above company until fully paid for" What is the status of the goods?

2. Is it amaanat or does ownership pass on to the purchaser? Is such a condition permissible?

3. Will the sale be faasid if such a condition is added?