Assuming that you are Fit to Tender, the simple solution is to properly qualify every tender. Here are some ideas:
- Go for quality not quantity - this will improve your hit rates
 
- Ask yourself 'can we win it? / is it really our business?'
 
- Consider the contract value - contracts are often not given to organisations if the contract value represents more than 20-30% of their turnover (are you big enough to service the contract?).
 
- Can you demonstrate working for similar types of customers doing similar work (and provide good references)?
 
- Location - are you close enough to service the work? Unless you have a specialised offering, it's often no good going for contracts out of your area.
 
- Too many other bidders? Are you just making up the numbers?
 
- Any PQQ requirements that you cannot meet eg ISO9001? If so talk to the buyer to see if it's mandatory.
 
- Existing relationship - you have good / bad / no relationships? What about your competitors?
 
- Competitors - who are you up against? Can you beat them?
 
- Is the customer going to change? Is it just a benchmarking exercise? Or a tool to beat the current supplier's price down
 
- Do the buyers allow meaningful communication?
 
- Consider resources / cost - can you bear these?
 
Time is too short to waste on tenders that you are probably not going to win!
