as a rule of thumb, don't rent at the maximum edge of what you think you can afford. people overestimate this when moving out (myself included) but usually the real max is 80% of the number in your head.

that said, renting the house is going to let you "skip" the experience of living in apartments, which is worth it. sounds like you're doing well too so good luck on ya

I work with a CPA and usually see this done through a SEP contribution.

you can learn more about that and other options here: https://www.irs.gov/retirement-plans/retirement-plans-for-self-employed-people