Borrowing against it is hard due to credit challenges.

You can not invest wisely without cash and cash reserves.Almost forgot....make sure your credit score is high, 750 or better.You need cash for a DP, closing costs and a reserve fund after you buy.

Probably due to bad credit but possibly a (maybe overextended) investor.2.

Only way this happens is if the note is private or held by a local credit union or local commercial bank ..if it rolled up in some large servicer one off buyers cannot or wont be able to do anything with it.

I have been offered 75% of the purchase price and 100% of the rehab, 80% of the ARV and 100% of the rehab but I have to have at least 15% of the loan and 3 months of payments in an account set aside for that deal, another one was $150,000.00 9.9% one time fee zero interest for up to 24 months on a revolving line of credit, and a few variations of these deals. 

Where I work and at most larger banks for the first 6 months it's all about purchase price and after 6 months you can refi based on the appraised value.If you have the track record and your ARV's are right I would either go in person or call local banks or credit unions.

I think that's because my focus is Class A or Class B tenants (minimum 650 credit scores and verified income must be at least 3 times the rent) - easy tenants.  

Both loan programs are great but each certainly have their own pros and cons, which really are tied to your credit profile and the property profile.

I am based out of California. 1st United services credit union offers heloc for 250k without any cost, but for 250k-500k I need to pay for closing cost and appraisal, costing me around $3500. 

My question is,  are there rules, regulations, qualifications or RESTRICTIONS on using a line of credit on a commercial property to purchase other properties?