Is there a specific duration I should be pre-approving an inquiry within?

However, if you feel you need their input earlier, you could offer to pay for their visit to walk the property with you pre-inspection.

Pre '2010', maybe just maybe it will lean heavier on the fundamental mechanics than specific processes. 

Quote from @Miguel Garcia: If I look into investing out of state should I look to get pre approved by a lender in that area or would a lender in my area be fine?

The improvements needed to be completed within the 180 day timeline, so I did a pre-fab ADU.

After 4-5-6 years then maybe roll them up into a small mulitfamily.Another option if you have the credit and some capital is to buy a 4 unit as owner/occupied and live in one and rent the other 3. 

The condo I'm selling in CA could sell for approximately $600k, and I was thinking of rolling that into 2 condo/townhomes valued at about $250k each, then doing DST for the remaining around $100 for the 1031.

If the proforma has the rent roll at $1400 a month, there is a discrepancy that could lead you into a bad assumption on your business plan.Also one caveat, be aware of physical delineations around the area like bridges or railroad tracks or a canal. 

Get in contact with a 1031 exchange company during the transaction and roll it into another property perhaps.

Quote from @Melanie Baldridge: Why I like investing in real estate more than 401(k)s.Both offer tax deferrals, but here's the difference:If you're making pre-tax contributions to your 401(k), then withdrawals = ordinary income tax.With real estate gains, you're paying capital gains tax (which is typically lower).Plus, RE investors get:1.