Having possessions are not sinful in themselves, but when they possess you then become a god to you then this is wrong. I struggles with this for many years as a professed Christian, I got myself in great debt with credit cards, unnecessary loans so I could have to best cars, house, filled to the brim with excess.
When I came to repentance and faith, through getting fired From long term professional carreer, I woke up, and donated and sold tons on my possessions, and fancy sports car, and home, plus thousands of dollars of things I collected, what a miserable mess I was!
God soon lead me out of my great debt and idolitry, as I submitted myself toHim, was led into a few jobs paying alot less that what I made before, but taught me to save, and give as He called me to, so now I live a modest life, a small apartment, all debts paid off, even my car is paid off, and kept some furniture, clothes etc.
Now I pay cash for things I want and need, asI gave away alot of things that were unecessary.
I enjoy camping in the mountians on occcasion, and have purcheced items for this, especially items for safety, and enjoying Gods great creation etc.
I felt guilty as I purchaced thngs back after I had so much, but now have my priorities in order, as I dont see having things or purchacing things such as clothes, going out for lunch or dinner on occasion, plus some items for camping, outings etc, are wrong in itself, as there were many wealthy men and women in the Bible who were blessed by God, were righteous men and women of God, and thier heart attitude towards thier possessions were right before God, just tempoary things we must be willing to give up and let go of when the spirit calls us to.
But if we worship these things, make them god in our life, forsake God and His truth to have these things, such as to be better than others, have the best car, or the nicest house, etc, then the motive to own these purchaces is wrong, and they become idols, instead of nice additions to our life, which are here today and gone tomorrow.
So be sure you are in the faith, have come to a saving faith through repentance and faith both proven by deeds, walk in His power and strength, we willl make poor decisions at times, or wrong purchaces, but it shouldnt deter us from our mission to love the Lord our God with all our heart, mind, soul, and strength!
I pray this helps,coming from a person who worshipped things over God and His truth. but now my life in centered on Him and His truth, enjoying things and purchaces in moderation, and correction mistakes I have made, being generious to share what I have with anyone in need, who asks, or is shown to me they are really in need, and I must give it up in a heart beat, as I did several years ago when I ran my debt up and up to apease my flesh,while my heart was still defiled,and double minded, serving two masters, so again for whom do you serve God or your possessions? Your heart and life(fruit) willl reveal this!