Why are some couples choosing to cohabitate before marriage? What effect does cohabitation have on marriage? Also, explain how financial status impacts marital stability. What other factors are associated with a couple's financial status?

Couples might choose to cohabitate before marriage for the following reasons:
The need to test whether future marriage can work: Through cohabitation, a couple can test whether their interest in each other can hold against the day to day problems of life. Things that might appear trivial, such as what side of the bed belongs to who, who does the dishes, or a partner’s personal hygiene suddenly become non-trivial when two people live together and can cost a relationship. If a couple is able to withstand these issues, then perhaps they’d want to marry each other.
Costs of marriage: Couples might want to avoid the financial costs associated with marriage, such as wedding or party costs.
Costs of divorce: Couples may want to control the inconveniences that potential divorces might have on their lives, should they marry. Since cohabitation offers most of the benefits of marriage, minus the divorce, many couples opt for it. This way they can avoid the emotional, social, or even financial costs that come with divorce.
Less responsibility: Cohabiters have less responsibility for each other’s financial support. Each partner usually operates more independently than in a marriage, and each person usually has more control over finances, time, or even decisions.
One effect of premarital cohabitation is what researchers call the “cohabitation effect,” where cohabiters are projected to have less satisfying marriages than their non-cohabiting counterparts. This is thought to contribute to higher divorce rates among these couples. However, research in this area is conflicting with some studies attributing these effects to cohabiters themselves rather than the cohabitation process. For instance, most people involved in cohabitation choose this route as they might have come from single or divorced parent families and hence naturally avoid marriage. They may also be more likely to have poor financial resources.
Marital stability is enhanced by a couple’s willingness to communicate effectively with each other and their ability to share concerns, joys, and sorrows with each other without fear. It is also enhanced by a willingness to resolve disagreements and transparency in the management of household finances. This means that partners must work together to secure their finances for the prosperity of the union. Like any other institution, marriage has a financial component; it will be difficult for a couple to forge an alliance as a team in the face of a poor financial environment.
Factors that affect a couple’s financial status include the general economy (here we can look at factors such as national inflation rates and interest rates), professional career, level of education, and skills (such as financial management skills, saving, or investing skills).
 
https://firstthings.org/cohabitation-good-or-bad/

https://www.psychologytoday.com/us/blog/sliding-vs-deciding/201407/the-hidden-risk-cohabitation