Newbie!!!

I would want to break it down into smaller chunks as the previous poster said. Diversify across platforms as well. I quite like BondMason as it requires almost no time and effort. One concern for me is whether platforms are financially viable in the longer term. LendInvest makes a profit (and is therefore more likely to survive), and is very simple to use...but the returns are much less than Bridgecrowd if I am not mistaken.

If it helps I've had good experiences with Bridgecrowd over the past 18 months, whilst the nature of bridging loans means you probably won't get your money back exactly when you're expecting it they so far have a good track record so I wouldn't panic too much at this point....if you're really worried tho someone mentioned on their board recently that they do now have a clunky form of secondary market if you ask them to sell the part for you. (If however you invested it in the current big loan I think you'll have to wait til that fills).

But as others have said with that size of total pot you probably want to diversify across some other sites with lower minimum bids. MoneyThing and ABLrate are currently my favourites for high rates (but if you're at all likely to have to worry about CGT do read the ABL tax faq). Collateral are small and relatively new but one of the few places you can still loan money on jewellery. Saving Stream are very popular, but make sure you pay close attention to discussion on their board if you do decide to go with them. Personally I'd avoid unsecured business loans like the plague...

My advice would be don't rush into anything, accept it takes time to build a diversified portfolio, and if possible stick with platforms with very liquid secondary markets to begin with so you can easily change your mind!

Edit - whilst remembering that future liquidity can never be predicted...
 

Very good advice there. The key to success here is diversification. Spread your money as thinly as possible, amongst as many borrowers as possible, and on as many P2P platforms as you feel comfortable with.  If you are starting with P2P I would suggest trying the bigger and better known platforms first, as they tend to be lower risk and easier to get into, before diversifying into some of the newer platforms.

Check any cashback offers on new companies as you may get a bonus for signing up through one of the cashback sites (of which P2Pmoney.co.uk is one) or through referrals on here.

There's a lot of good advice to be had on this forum, both in general about investing, more specifically about P2P investing, and commentary and opinion as regards different platforms and the loans they offer.

You could do much, much worse than spend an hour or two reading through some historical threads on here (though normal provisos about not being investment advice and caveat emptor apply).

Welcome to the P2P world
brannick, this is probably one of the best places to start your journey. In terms of diversification, it could be a good idea to also look into platforms with a secondary market where you can pick up chunks (or smaller bites) of loans that you might have missed. 

Just wanted to introduce ourselves as we currently have a live loan auction (London Residential Investment) going on paying 8.75% and you can invest from as little as £500. If you need any help, feel free to give me a shout.

trading.relendex.com/marketplace 

Relendex, the individual is new to P2P, has £20k total to invest from a non-ongoing source (inheritance) and you have suggested to them that putting at least 2.5% in the product mentioned that requires non-trivial risk analysis is appropriate. Both the amount and their level of experience suggest that they are not a suitable customer for this loan. Do you really think that your financial promotion to this individual was appropriate? With reference to COBS 4.2.4 have you made the required disclosures in your post, using this medium which does provide you the space to do things like telling them that their capital is at risk, what the charges are and whether they have any FSCS protection? Did your post give a fair and balanced impression of the short and long term prospects for the investment that took into account the needs of an individual inexperienced in P2P and presumably also inexperienced in evaluating property lending deals?

Setting aside the fact that the posts will almost always be financial promotions, posting like that in a newbie topic to promote a platform is unwise. It inevitably makes Relendex look bad when the newcomer is really seeking the thoughts on those more experienced with P2P. Unless specifically asked or mentioned and with a correction to make it would be better in almost all circumstances for platform reps to stay away, tempting though the topics can be.

A good deal less care may be appropriate in sections dedicated to individual platforms or to more experienced investors but newbie topics are particularly unwise based on the inexperienced status of the potential investor. It's inviting a future complaint and possible platform liability for losses that no amount of terms and conditions can effectively disclaim.