Feeling lazy to carry out extra ibaadat

Q: I think I'm a liar and a munaafiq because the lovers of Allah Ta'ala love to worship Allah Ta'ala. I sometimes get tired, lazy and there are days when I feel like I just want to relax and give it a break.

Many times it happens at tahajjud time where I do not want to get up, I have to force myself, and sitting from tahajjud to ishraaq is a very big problem.

How can I overcome this problem of laziness. Isn't the lovers of Allah Ta'ala cannot get enough of worshipping Allah Ta'ala? There are days I just want to sit and do nothing extra. How can I overcome this condition?

Receiving haraam money as payment for a loan

Q: A person gave a loan from his halaal money to someone with a mostly a halaal income. Later, the person who the money was lent to took a new job in which they earn a mostly haraam income. Is it haraam for the lender to be repaid by the person he lent money to?

Will such a repayment carry any of the spiritually destructive side effects of utilizing haraam wealth? And if there is any evidence from the ulama and fuqaha on this matter, then please share because I could not find anything about this online. 

Taking possession of an item before selling it

Q: I want to sell items (mostly food) via social media. e.g. tubs of biscuits, sweetmeats, pastries etc. I do not make these items nor keep any on hand i.e. made to order. The items will be procured from multiple home vendors. I will advertise these items via social media and interested parties will contact me to order and pay me for the items. I will then order the items for the buyer and the buyer will collect from me or from known pickup points in different areas. I will be paid before I have the items in my possession and I will pay the baker once I collect/receive the items.

Will I need to get the order, buy/pay and have the item in hand before I accept funds from the buyer? Will this type of model be permissible? If not, what will I need to adjust in my model for it to be permissible?