Financing for investment properties

[Manish Shah]

I am looking to get some advise from experienced investors or mortgage brokers regarding obtaining finance for investment properties. Also, need some advice on formation of partnership which gets complicated when you have 3 to 4 investors. Here are my questions.

1. I understand that one cannot have more than 6 mortgages at any given time. If I am looking to purchase 15 to 20 properties (approx 150 to 200k range) how can I do it?
2. How can I go around another limitation where I cannot exceed all my loan payments 45% of my total income. Why cannot I leverage the assets I have to borrow more?
3. I am looking to form a partnership with 3 more people (4 together), how can we go about obtaining mortgage? Does each of us need to be on the mortgage (ideally yes as each of is owner and I understand we cannot get loan on LLC)? If not, how can we form the partnership and get the mortgage? Each of us has a job and our spouses also have job too. Each of us have at least one mortgage (i.e. on our primary residence). Who can we consult for advice on such issues (CPA, Lawyer, mortgage broker etc)
4. One of the mortgage broker we consulted advised us to take mortgage on each of the partner's name (one partner one property) and have the property owned by the LLC with that partner. After the mortgage is secured, add more partners to the LLC (effectively making it owned by each of us 25%). But it does sound right that one partner has the liability (loan) and all other partners share ownership without liability. Do you think we can have a separate contract between partners committing each of us to each loan even if the loan is on one partner's name? Is that possible?
5. We intent to buy many properties. Does it make sense to have each property owned by a LLC? Will this be a big overhead (to own 20 LLC, tax filings, K1, cost of accounting, bank accounts etc)? Forming LLC with four partners means we will not be eligible for a pass-through structure for the LLC.

Appreciate anyone with knowledge to reply to this post.