The general advice goes like this; If your work offers a match on a 401k then contribute up to the match. If you have more money, max out an IRA. If you have more money, max out the 401k.
If your health plan is a high deductible plan with an HSA you can also contribute to this. They are designed for health expenses but they can also serve as an additional tax advantaged retirement account.
Beyond that you’d be investing through a taxable brokerage account.
As far as what to invest in, S&P500 index funds are usually advised since they tend to capture the overall average returns of the market. Target retirement funds are another option if you want a set it and forget it option that will rebalance to less risky investments as you near retirement age.
LED’s can be very particular about their dimmer. Unfortunately it’s not enough just to go to the store and pick up a dimmer switch that claims compatability with LED’s .
Fortunately most LED fixtures/bulbs come with a list of recommended dimmers, at least if you stick with larger brands and not cheap LED’s from Amazon.
I know a few in my house require ELV dimmers and those sell to the tune of $50/ switch whereas others work fine with a $10 MLV.
Meanwhile my under cabinet lights explicity state not to use an ELV dimmer and to only use MLV or risk damaging the unit.
Are the posts set in cement? Is the house new construction where the ground may still be settling because it wasn’t fully compacted?
People often skip cement footers for fence posts which might be okay if the soil is well compacted and the type of fence isn’t sensitive to movement but the one place you should always use cement footers is around gates.
If you already have footers then my suggestion would be to set them deeper. It could be poorly compacted soil or the type of soil that’s the problem in which case the only way to combat it is to dig down deeper so the footer reaches more stable soil.
There’s really no need to replace the decking unless it’s damaged, regardless of it’s age. It would be an unnecessary expense, and a large one a that.
That vent pipe is PVC which tells me it’s a lot newer than this house so my guess would be that whenever that vent was added or replaced they destroyed that board in the process. Regardless, the roofers should have corrected it. It’s possible they just forgot to circle back to it if this was the only issue.